Pay Range is used in Boulder at Press Play and CU campus. When you get close to the game it will confirm the game with an image of it, so the buyer just needs to pay attention. The only issue I've heard is that it is only able to process full credits, so the 3 games for $2.00 on a $0.75 game deal doesn't work all that well... you wind up putting in 3 swipes ($2.25) to get 3 games and then you have a $0.25 credit left over, so if you like to do that, supplement with quarters to top it off.
There is a fee to the operators similar to a credit card transaction, so anyone truly concerned about such fees should probably not be using credit cards for anything, ever. There are a few benefits that have not been covered here. Operators may get a little extra bump as if someone runs out of cash they no longer have an excuse to walk away. I'm one who regularly stops playing once my quarters or dollars run out, and I'm sure there are others. Probably more useful is the ability to put all games on free play, for example a barcade can now run a happy hour every day from 5-7pm with freeplay, $0.25 Tuesdays, etc. The ability to run specials for customers is probably worth it regardless of anything else, but Pay Range is still limited in that area.