Sexist? Or does this prove a point?

This morning on my commute to work, I heard on the radio about a bar in DC which is charging women .77 cents on the Dollar for every drink they purchase. There reason they said is to compensate for the fact that women working the same jobs as men only make 70% of the salary men make. I found this interesting, and I know my opinion, but I really am interested in seeing more opinions on this topic. Thanks!!