I do see value in this for busy people. Who want to receive message by urgency. So yeah, if it's urgent then only contact me like use case certainly exists.
I actually liked the concept of pay to send message. Want to contact a star no problem. Pay the highest or set number of credits and you are in.
Additionally, the sidebar ads in google or facebook are auctioned off to the highest bidder. So users are already receiving improved targeting based on pay-to-send. The only problem I see this solving for users, is that they collect the money instead of facebook or google.
That is very little money on a per-user basis. So it's not solving a meaningful problem.
I agree that there is huge potential in "pay-to-send." But this marketing appears to be off-the-mark.