My friends parents hate me?

Today my friend and I were hanging out and I asked her if her parents didn't like me because they would always act weirdly around me. Like the dad would always make 'jokes' about me being fat (which i'm not...) and i would just laugh it off and change the subject. She told me that she heard her parents talking about me and they called me a sleazy nomad (homeless person) and all of this other stuff. I am always nice to them, I have never done anything to offend them and i dress modestly and I'm not a bad kid. I know that not everyone you meet is going to like you, but i just don't get why her parents hate me so much...