Obesity, skiny, tall, short, unibrow, hairy, flat figure

[A-Man]

Let me put it this way: People in Germany speak German.
Obviously, not everyone in Germany speaks German - there are immigrants, tourists, the mute who can't speak etc, but would I be wrong to assume that the majority of people I meet there would speak German?
In the same way, if I'm looking at a large group of obese people, would I be wrong to say that the majority of them are obese because of bad lifestyle and not genetics etc when the statistics back this assumption?

Again, I want to stress that looking at people as a group and looking at individuals is a very different matter, largely because individuals don't have a sample size (plus the obvious emotional factors). That, and making a generalization does not mean declaring a universal truth.

But that's different! Here is another example that has more to do with the generalization we're making: All the filthy (and by filthy here, I just mean extreme) rich are scammers, smugglers, or people who work in an illegal field such as drugs trade.

There is a huge difference between making bland generalizations on something that is considered neutral, and something that is negative or offensive (or even positive). While it's true that the majority of the filthy rich's money can return to the reasons above, there are still those selected few who made their fortune legitimately. I still can not say "Filthy rich people made their fortune by resorting to dirty means", or am I wrong?

Edit:

Judging an individual based on a group is pretty messed up. Saying that a group primarily consists of lazy people is not.

Indeed. Note the use of the word "primarily". This also means we can't let a first impression be based on that generalization. I agree that obesity is a problem, and any move doing what "HAES" is doing should be countered. And please pardon my impulsive misunderstanding reply.