Quite sure people would pay. Seen a few girls who have a pay for 'premium' snap account. I know Orion does. Aussie to US$ conversion makes it to expensive though for me.
Some girls do Snap chat for money, but I think it totally changes the dynamics of the relationship. All of us guys perve a little on this site, but mostly we appreciate beautiful women expressing themselves, and showing off their bodies in a safe manner. Pay snapchat and webcams take it to a different place and level. Just my 2 cents.