PS: I'm working on reimplementing the functionality of that app at https://github.com/sgnn7/Android2Linux which can help you figure out how to do it manually if you can't find it.
- Large number of people will not redeem the coupon (forgetting, unavailability, etc)
- Repeat business will increase
- Influx of money now is better than later for a business (to buy better mass-production equipement, etc)
I would venture to guess that he will do fine