Anyone using CheckPoints ever win anything from their slots feature?

I've been using their receipts feature for just about everything I buy lately - pretty good, get 20-25 points for the first two receipts I scan in a day, and then coins if I scan more. The coins are strange though - seems I can only use them for their slots game, but I haven never won anything on the slots before. Anyone ever win, or is it not worth the time?