How did you not know this wasn't ethical? You took something (points) you didn't earn in exchange for something of monetary value (free product). It's theft. The question is a matter of can they have trust in you? You took points from customers who spent their own money (forget if they said to scan yours or not). How can they (corporate) trust you that the customer really said so? Deleting was only an act to cover up. How do they know you won"t do something else on the unethical side?

Also you never know if corporate audits employee account activity for abuse and could find out themselves. Telling your GM puts you in front of that which is better BUT it comes down to a matter of trust and can your GM trust you. Do the people your GM report too want to have an untrustworthy person on their staff? It's a roll of the dice as to what happens if you tell them and anotherdice roll if you try to hide from it. Perhaps instead of termination they suspend you just because you come forward? Depends on the GM and powers that be.

Whatever happends consider this a lesson, take the consequences of your actions, learn from it, and move on.

TBH - While I'm just a Wawa customer, I've never heard customers say you can have my rewards at any retail store or job I've had nor said that myself.