There is no problem, except that there are a lot of games coming together at the same time.
Rangers have to take the money out like this, to ensure no one pulls a fast one by changing their banking details which would then start to incur further costs to the club. And it insures the club against people who were on the CCCS pulling out of buying a ticket for a dead rubber because they no longer want to go.
People are going to be hard up, but for fuck sake we knew this would happen if we qualified. Why the horror?
Or the club can simply put all tickets onto the market at the same time. If you can afford it, fine. But folk would moan about that.