There are a couple of Nash-esque plays, coupon combinations that remove any challenge or threat from the game... but it's super fun until reaching that point! Great choice of audio, wonderful animation juice, enough interplay between coupons to have emergent strategies without becoming more complicated than it's 'accessible' aestetics suggest. Great stuff!
(Breaking the game after the ... er... break.)
# 1 - 2x $10 off, 1x Double Down, 1x +1 Round, 2x 20% off, 1x Flat Rate Multiplier. I quit shortly after this one - my remaining rounds are growing over time, and the rate of cost growth v my income suggests this is sustainable another 45 rounds or so... which is too long for me to keep doing the exact same thing over and over.
# 2 - "Bulk Repackaging" + "Flash Sale" = 2 coupon win on the first round. Add a +1 Infinity Round coupon and even the round counter is foiled, leaving two coupons free for whatever. I'll eventually pick up a second +1 "Infinity Round" so I can boost income AND remaining rounds, but I'm already to the point where it's +$20 a transaction and infinite transactions remaining, regardless of anything the game throws at me.