Nice pictures but definitely not 15$ nice in my opinion. I always compare it to actual magazines. Maxim,FHM and Playboy, none of them were 15$ and they were monthly and had more than just one model (although less pictures of each one). Digital Distribution costs nothing, and aside from MAYBE a photographer (although these days you don't even need one of them, if you look at some of the Rachel Cook Selfie Stuff in Wtvr...) you have little to no cost to make such a "Magazine" which is basically a small photoset.
Should she (and the other models) be compensated? Sure, it's how they make a living. But unless you're a superfan you're not gonna shell out that kind of money for 10-20 pictures, especially with the economy the way it is at the moment in a lot of places. Just my 2 cents.