I feel kind of bad for your friends. Imagine going to a different country, to DISNEY WORLD, and all that can be taken away from that is that people are fat? When I go to Disney, I am rarely noticing other people's bodies...barely a blip on the radar. It's unfortunate to not see what a blessing it is to be part of the magic and to see others enjoying their day, no matter what they look like. Life is far too difficult to nitpick how others look.
I visited the UK and Paris and I really did not notice whether people were skinny, fat, black, white, had poor dental hygiene, lacked fashionable clothing, etc. Just not the purpose of my trip, I was far too busy taking in Cotswolds or staring in awe at the rolling green hills of the Parisian countryside.