Aren't most amateur hackers retirees in nursing homes with a lot of time on their hands? Nice to see an application aimed at a different audience (young women).
Programmers seem to work for free on Linux and other projects, while designers seem to be more eager to get paid. Given these common memes, people may think that programmers are eager to do any kind of work for fun.
Here's a proposal: use your email address. Period. No password. Take your average bulletin board--you're probably not going to use your email address as your nym anyway. Even if you do, what do you lose if someone impersonates you?