Have you considered not using the same pricing on all the games? Price one at a quarter, a couple at 50c and a few at a dollar. This moves the customer from the question "yes/no?" to "which one do I play?".
-Rob
-visit https://www.kahr.us to get my daughterboard that helps fix WPC pinball resets or my Pinball 2000 H+V Video Sync Combiner kit