I'm not offended. It's true. When my mom and I were travelling through Europe, it became almost embarassing esp. in Venice where everyone walks. Nevermind Japan where my sister stayed for a year. If people think the stereotype about fat Americans is popular in Europe, they need to go to Japan LOL.
One would think that given the example that they used, it follows that they were trying to convey the notion of Americans as stupid, I think. After all, what rational person would eat at a fast food place that puts their health in danger?