This is horrible, and interesting! The biggest group to stand to make money off the back of Facebook is probably spammers, by charging a dollar they're either going to get really good spam or it'll still keep them away. Of course, if the spammers can Nigerian prince a few fattened gooses they'll take the $1 price as the entry fee and deducted it from the profits.
Puzzled why anyone at Facebook thinks this is a remotely good idea, but you know, business model.