Ok so the most shocking things have probably already been said, but I have to add the few stories I remember from my many trips over the years.
The last couple years was the first times I really realized and encountered "road rage" in WDW. People get on those
ECV's, wheelchairs, or strollers and just plow people down. Well one day I'm crossing the bridge to Tomorrowland and that bridge gets particularly crowded during the day. I keep feeling something banging into my ankles/legs, I turn around and see one of those hard, plastic strollers behind me being pushed by this woman that looks very irritated with her baby inside. I could barely move across the bridge cus it was so crowded so I don't know what she was thinking was going to happen with her constantly banging the thing against my legs, I kept trying to tell myself it was an accident. Until I got one huge hard bang against my legs, I almost fell on top of her baby! She hit me so hard that it threw me off balance in the midst of this crowd and she was willing to get her baby crushed to what, move up 2 feet? Luckily I didn't fall or anything, but my god, is it really that much of an emergency that you need to potentially injure people including your child? I'm 5'10 and weigh a lot more than people think, I would have crushed her baby without a doubt. The lady just gave me a dirty look when I turned around and looked at her in shock.
Then I was waiting in line for those rockets in Tomorrowland, I can't remember what the ride is called off hand, but anyway, the line can take a really long time I've noticed on every trip (which makes me question why I keep riding that crappy ride). So there's this little girl in front of me alone which is odd, but she's maybe 10 so I'm thinking maybe her parents are waiting for her to the side. Well in the midst of waiting in this hour long line, various members of her family keep cutting in line to come talk to her. And when I heard them speak, let's just say they were rather "ghetto." I couldn't believe the huge attitude coming out for this cute girl. Her brother (probably around 14 or 15) then drops off this toddler with the 10 year old and tells her to take care of it. She proceeds to drag this cute little 2 year old around by the hand yelling at him to hurry up. He obviously can't walk very fast and didn't know what was going on, he just waddled around chewing on his hand staring off into nowhere, so I had to help him along and wait for him to catch up to her, but of course this whole process irritated everyone in line behind us. Then right as we get to the open part of the line where they are about to take you up in the elevator, she starts yelling for her entire family to come over, so about 10-15 children run up and crawl under the bars and fill up the area before the elevators and the CM's let this happen! They even waited while the children went and got an "adult" to ride the ride cus the toddler was too small to ride with all of them cus none of them were older than 16. So they bring their 20 year old brother (they told the CM's he was 20 is the only reason I know this) who was wearing incredibly baggy pants and a t-shirt with marijuana leaves (he looked responsible!) who looked completely annoyed by having to go on the ride (how about the entire line of people who were annoyed at having to wait for these guys!). I end up getting shoved into the elevator with them which was incredibly uncomfortable as they're all fighting and pushing each other. We get up top and wait for our turn to ride, as soon as those gates open they just push me and the only other person not with their party out of the way to go claim their rockets (this poor man had a toddler with him too that almost got trampled). What particularly shocked me about this situation was that the CM's watched and allowed this to take place.
Another incident occured when I was a young teenager. My best friend and I got in line for SM on a very hot and crowded June day. We know we're going to have to wait for an hour to two hours, in fact we had already waited about half hour by the time we got to the part where it goes under the railroad (now where the fast passes are handed out and where the line usually starts). BTW, there were no fast passes back then. Anyway, so this CM comes up to us, a young teenage boy, and starts talking to us. He's flirting with us and we're just complaining about the lines that day and how hot it was etc. and he tells us we don't need to wait in line. He tells us he can get us on without waiting and all we had to do was go up the exit and tell the people "baby swap." We were very hesitant about it cus we didn't know what that meant, we obviously knew it was not on the up-and-up, but after him sort of harassing us about "just doing it" for awhile, we decide to go for it cus he assures us it will be no problem (plus we were like 14). So we go into the exit and tell the people working there "baby swap" and of course they ask us where our baby was. We had no clue what they were talking about (of course we assumed baby swapping had something to do with babies), but we didn't know what it was exactly. Needless to say they "busted" us, but we tried to explain to them that the guy working there told us to do it and gave him his name and stuff then ended up having to go to the end of the line again

. I hope he got in trouble.
My gross story happened in line for the Imagination ride in Epcot. A kid not too far in front of us in line just vomits everywhere. He covered the entire width of the walkway so no one could walk around it and everyone had to hop over it. (I think he had sausage pizza for lunch

). Needless to say, the mother of the child didn't take the child out of line or even have someone in her party go tell a CM to come clean it up, she just pretended like nothing happened. When we got to the front of the line we told the CM's about it (wasn't too far from the front).
I luckily have not been aware of any urination incidents or the like. One thing that does gross me out though is when children pick their noses. I've seen them wiping their boogers on the rails so I NEVER touch them. I expect this from children, but what pisses me off is that their parents see them and don't correct them or even acknowledge that what they're doing is gross. Children won't learn their lessons about right/wrong or in this case just basic hygiene if they're never told what they're doing is inappropriate. It's just pathetic if you ask me on their parents parts to be so apathetic to the behavior of their children in those parks. Of course that's nothing compared to the children who run around screaming, tearing things up and putting others in harm's way. AK was the worst. My sister and I encountered so many kids running rampant with what appeared to be no supervision. The worst is when they stop suddenly in front of you when you're walking cus it causes you to almost fall or trample them and then also cause people behind you to bump into you. I'm pretty tall so it's easy for me to miss small children under me.
My sister and I were in line for that safari thing and this little foriegn kid (not sure what country but he was Asian and his parents weren't speaking English). They were walking in front of us in line and this kid just kept stopping randomly as he swung from the rails, holding on to both sides so no one could even pass him. Then he would run up and down the line, even though the line was continually moving and his parents wouldn't even care that their 5 year old just ran off from them, or actually I don't think they were paying attention to even notice. I wanted to tell him that his child ran off but he didn't seem to care and well the whole language barrier thing. At one point the dad realized his son was missing and started freaking out yet they still continued in the line (/boggle), when the kid finally ran back up the line to them he gave the kid a severe scolding in some language. I wanted to tell him that it wouldn't have happened if he had been watching his son as much as my sister and I were

.
My other main "shocker" for WDW or DL is going with people who have never been there. I LOVE taking people who have never been there cus it's neat to show them around and see them enjoy themselves cus it's all new stuff to them, but sometimes I've taken new people who want to leave after 2-3 hours. I just don't get it. First of all, who doesn't like WDW or DL?

Second of all, who pays $50+ for a ticket and wants to leave after 2 hours?! This has happened to me on a few occasions. I try to make people rough it out longer, but it certainly spoils my day when that happens. So now I only like to go either alone or with people I know really love it. I know it's odd to go to WDW parks alone, but I almost have a better time that way, although some of the longer line waits can get lonely. However with single rider lines and fast passes, I never end up waiting long for stuff anymore, especially when I go alone and know the tricks of timing.
My nice shocker was these 3 little kids, probably ages 3-5 were standing next to me and they told their mom I was pretty and that I looked like Cinderella. I felt like hell from drinking late the night before, lack of sleep, and lack of make-up. That made my day though

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