Dear intelligent people: Why is. Or was. Big butt an insult?

Growing up kids in elementary school insulted people by saying they had a big butt. I ve seen in in TV shows. Characters insulting another character saying they have a big butt. Just a few minutes ago… Man my short term memory is SHOT. I was reading something. Like a comic type thing. Someone said to another person. Something like "you big nose, crooked face, buck teeth, cross eyed, ugly ***, unintelligent, big butt, reject". It was like a long list of opinions with big butt in the middle. But why is it an insult? I used to think it was bad until I hit puberty and I realized a woman with a big butt is the best thing in the world. If I had to pick 3 things I could live without other than food and water it d be woman with big butts… And who the **** cares about the other three. Give me your opinion on this stupid question please. Why is it used as an insult sometimes? Am I of a small group of people that love huge butts on a lady? Are the people that use it as an insult just jealous? Are big thighs and butts a sign of a fertile woman namely big thighs being good for birth? And everyone knew that… Or had it programmed in their brains until western society in the 50s when people started being pricks about big butts and just recently our more sexualized mainstream art has reminded us of the pre 50s prick mentality? Does the shoe full house Really need to come back? I mean really? Will Rebecca s *** be phat in the episodes? Anyways I ll appreciate any answer thanks.
Added (1). Her a s s why the hell cant you say *** on here Jesus. I'm offended that you can't say ***. My dad was an ***. And I'm proud of where I come from.
Added (2). I meant show**** "Full House"
Added (3). I meant show**** "Full House"
Added (4). My iPad ****** up and put that last update twice. ******* Steve jobs.

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