How about this... loved this.
We brought pool toys with us from home for our LO's.
So for some reason all the kids thought it was their right to come take these toys from my kid. Note the girl in the picture with the watering can.. not my kid. That kid took the toy out of my baby's hands. Often they would take all three pieces and leave my infant crying.
The WORST part was not ONE parent said a stinking thing. I spent the entire week retrieving toys for the girls. I would normally make them share... but geez! And the worst of the worst was a Dad who watched his kid come take all three pieces from my baby, she cried hysterically and the child took the toys over and plopped down with dad and he played with them with his kid!!!! While mine sat there crying. Like it was their RIGHT!
One mom after I went and got them back said "That's fine! We'll just go buy our OWN toys from the gift shop!" Of course she came back empty handed.
Anyway... I thought it was rude of the kids and the parents!!!
Oh, I hear you on this one! It hasn't happened to us at WDW, but it happens at the rec center pool in my community. It's sort of an unwritten rule that toys left at the side of the pool can be played with by anyone, just put them back where you found them when you are done, or when the owner is leaving and asks for them back. Most of the little ones are good about following this rule, but occasionally, kids will grab them right out of the owner's hand, or take them out of a pool bag on a lounge chair 20 feet from the pool, with parents seemingly nowhere to be found.
One time, a little girl was playing with some of my dd's toys, which was fine, but then her mom got up to leave and started putting our toys in her bag!

I went over and asked for the toys, and she acted like she didn't remember which toys were theirs and which weren't, and like I was the weird one for caring about some cheap little pool toys.

Yanno, I know they're cheap, but if I had to replace 2 or 3 of them every time we went to the pool, it would start getting pretty pricey, and besides, so what? You don't just take other people's stuff, no matter how cheap it is!