Whenever I go to the US (and I go mostly to NYC), it's not the morbidly obese people that surprise me, it's simply the average weight of everybody.
Most guys have a beer gut. Most women carry a little too much around the waist or saddle bags. These people are often young and look quite confident in their looks. Kinda odd to see a flabby repulsive woman approach you like she's the sexiest thing in the room.
You can tell that what is "normal" is to be overweight. One (quite good looking) girl told me she was teased in school for being thin. She was the oddball.
Well, I'm going to take my wine-gut and go talk to someone else then, thank you very much.