Why are my friend's parents acting like this?

Alright well, I’m here typing, because I can’t figure out why my friends parents are wound up so tight! There is this girl, one of my good friends, the same I won’t say. She has this awesome pool in her backyard that a lot of people in our neighborhood [including me] like to swim in. Her mom thinks that’s the reason we are friends with her. Is she phsyco? She actually thinks that im using her daughter? Yeah right. I’m not that low, come on lady. I can hear her mom on the phone EVERY time I call because shes so freakin loud, when I ask if my friend cang hangout, she will say ‘’you guys arnt going swimming! nah nah nah!” It’s rude, actually and im not def. They go to a private school and she has two other siblings. They have to call her parents “Sir” and “mam” and its P A T H E T I C! This is really starting to drive me nuts. You can’t be friendly with their parents, like if I was just joking around about something. I don’t even think I’ve seen the women [or her dad] smile. They just go around like they have sticks up their butts like “oh we dont approve, thats not up to OUR standars, meh meh” In a way they judge people. I was going to my other friends party, and she was invited too. Her mom told her that she can’t come unless I was there, do I LOOK like her babysitter to you? im only a year older than her anyway! They other day, her dad came in her room and saw a candel on her desk. He goes “excuse me?!” and she went “I promise sir, I never lit it!” Is it just me or is this crazy? That’s not the way I live I don’t know about you! Why are they so minipulative?!