It is best for them to make their money through the gem system they already have with the timers. If you want something open, then you must pay a great deal to get enough gems to open it frequently. This is probably what the people at the top of the leader board do, and I think of it as a sort of patronage similar to a YouTube channel. Their names are at the top of the heap which gives them recognition, and if they play against each other well during the events, they get to have an unstoppable set of girls as a second reward for spending the money, and the rest of us get to play for free.
I fear the system you propose would work too well and would encourage undisciplined people to do terrible things to their accounts.
I still must agree that increasing the prices was bad. It was especially bad for the refresh. I never used it except by mistake when I first encountered the Pussy Market (I thought it gave you 500 coppers... how stupid of me!). If it were 50 coppers, I would not use the refresh, even if it were five coppers, I still would not use it. The fact it is 5000 coppers shows me that the business people in charge of this mechanism are out of touch with the incentives they have set for us!