Hm, pretty nice argument. Though I do kinda agree that there is a lot of overweight people. But being offended for it isn't really helpful for them. Either they'll take it harshly and feel worse about themselves or they'll just ignore it. It doesn't happen very often that they'll take the insult and work on it. At least I haven't heard of it happen very often.
Actually, I also think that there is such a think that you can be born with a "fat gene." I mean, you don't come out of the womb fat, I think you just grow up into being overweight. Then again, I don't exactly know.
Eating healthy is always good though. It's only on the choice of the person's food. Sure, we can encourage them to eat healthier, but they can just ignore it or take it.
So, are we Americans too accepting of fat people? I honestly don't know. News keep saying that we are overweight and telling us how to fix it. Though it's just been with us so long that we don't really care anymore. All we do now is just make fun of fat people. Most of us do. Not all.