I've said it before, and I'll say it again....WDW transportation works for the general masses....for the vast majority. Are there going to be some guests that aren't going to be able to safely, or happily, use the buses? Or even perhaps the boats and monorails for that matter. Yes, there will always be a certain number of people that have an issue. And those guests need to take it upon themselves to find alternate transportation. You can not mandate who gets to sit and who doesn't. I am 66. I didn't need a seat on a moving bus when I was pregnant...I wasn't ill, I was pregnant. Carrying a child? That's your choice. I've been to WDW with a 5 y/o..and yes, she got sleepy. If she didn't get a seat on the bus, she held on, for dear life, and dealt with it.
Those that may have some challenges can either board with their ecv/wheelchair/whatever, or if they don't use one, can decide if it's worth it to wait for the next bus in order to be sure to get a seat.
What gets my goat? Those that take a seat in the 'handicap' seating, and then get bent out of shape when they are asked to move....I've seen guests arguing with the driver about this. One person even said it was first come, first served. I, sort of quietly, mentioned to the person next to me (we were both standing) that evidently that guest couldn't read the signage above her head...that stated they may be asked to move!!!! That lady was not happy with me! Yeah, I tend to become the bus monitor..I can't help it. There was an empty seat close to me, I was standing, and I saw an older woman up front....asked the man next to me to see if she wanted a seat! No one offered their seat to her....and there were probably 3 younger men (40's-50's) sitting nearby. They looked a little ashamed at that point. The woman declined the offer though...said it wasn't worth trying to get through all those standing between her and the seat!
Or those that board a crowded bus and just stop short of that rear door....then I have to be a bus monitor again...'Excuse me please, trying to get to the back as the driver asked..excuse me please!!!!'.
Then, there was family that decided the rear door was open for them.....no matter what the signage said!!! They plowed right on, complaining when people didn't move aside for them, and the door started closing on one of their kids!!! The young man next to me, beside the door, turned to me and said, in a loud voice..'Oh, I guess that do not enter sign wasn't for them, it's just for the rest of us!!!!' Man, one of the women gave him a filthy look. I just looked at the sign and shrugged my shoulders. Nope, they weren't happy with us.
In all reality? You do what you want to do. What you, personally, feel is the right thing for you to do. I know there were probably many people that thought my dh should have given up his seat. But, he was headed to a knee replacement, and he really wasn't safe standing on a moving bus!!!! That would have been an accident waiting to happen. So he stayed seated! You just don't know what someone is going through or what issues they may have. Don't make snap judgements based on what you 'think' you see. I'm 66. I don't look even close to that age. I don't act close to that age. I don't need a seat, I actually prefer to stand. Others have different needs. No one should board a crowded bus and expect someone to give up their seat. It is each guests responsibility to take care of their own needs and the needs of their family. If there is someone in your group that just can not stand on a bus, then you have a choice....wait for the next bus, or take alternative transportation. Is a cab going to cost you money? Sure it is. But, you have to know, before getting to WDW, that you may possibly be faced with paying for a cab at some point. You should probably budget for that. Or just rent a car. Or stay at a resort that gives you alternatives to buses.
But you just can't count on the kindness of others to get what you need. Yes, there are plenty of guests out there who will do whatever is needed to help others out. But, there are also those who are unable to help...for reasons that can vary.