You don't have to send in a request form, you can signup yourself.
I think their US traffic is shitty, but that's not the only country they serve ads to.
I convert lead campaigns at about the same % as facebook ads.
If you get clicks by mistake, then it's time to revise your ad copy and make your action button say something different.
Their ad delivery system has a serious exploitable flaw which is bad for publishers but good for advertisers.
But ya, someones probably going to steal your password and blow your budget, so stay away from social media!!!