Weird names?

I hate it when people have weird names for stuff.. Especially when you're a mature adult. It just bothers me so much.. Why would you call it a hoo-hah when you can just say vagina? Why would you say wiener or weewee when you can just say penis or dick? Why would you say toot or poot when you can just say fart? I just don't understand... If you have a child around I kind of understand, or if you ARE a child, but teenagers and adults just saying things like that? Cmon now...