Why don't some overweight people Seem to care about their body at all?

I know people who are overweight and just don't care and I just can't understand why. To me it seems like a self defense mechanism. Like for instance I saw a Facebook meme going "yeah I'm into fitness. Fitness this burger in my house." In a way it's a funny meme. But in other ways it kind of disgusts me. I'm not judging anyone. I'm just not understanding why they think that way. I'm not talking about people who are like 300 pounds but people who are clearly overweight with a gut and out of shape. I know a friend who when i mentioned that eating healthy and dieting can be difficult, he said "i know. That's why I don't do it." I just don't understand. Do people really lack that much discipline? To me it seems like a defense mechanism. "If I tell people i don't care then they can't give me crap for it."
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+1 y
by the way that says mouth. Not house. Typo.
Why don't some overweight people Seem to care about their body at all?
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