Parents won't let me start a GoFundMe?

Hi, I was trying to earn some money recently, when I came across GoFundMe. I heard you can start one for personal uses and for creative arts, and that’s exactly what I need. I want to film a movie, but I need a bit of equipment. When I asked my parents about this (I asked them because I’d have no way to cash the money out) they said no. Why do you think this is? There’s no way to earn money for me and I don’t get an allowance. What can I say to convince them to let me do this?