Going to the Olympics is like vacation for these guys, not to mention they've been cutting weight/training like madmen for the last 8-12 months. On top of that, they're likely burning thousands of calories with their daily routines. And you know what? If I just won a fucking gold medal at the olympics and someone is offering free food, I'm going to eat whatever the fuck I want. Even including 20 items of McDonalds a day, their weekly caloric intake is still 1/10 of the average ham.