Could it be because of culture. I grew up in a particular heavy African American city. I played basketball almost everyday in grades school and they talk smack about your mama and stuff. I’m use to it now and I learned a few good come backs.
example: your Mama is so hairy Bigfoot took a picture of her. Your mama is so fat when she turns around it’s her birthday, or mama is so fat I told her to bow and weave she thought I was taking about kfc.