This question arises from the answers given in Is it illegal for a store employee to do this with payment? and What power does an employer have over gratuities/tips?
To recap, a retail store does not accept payments in cash. They only accept payments by debit or credit cards. If a customer only has cash with them, so store employees accept the cash and pay with their personal credit card. No change (if there was any) is returned, and the employee keeps it as a tip in a sense.
As an example a customer buys something that is $19.50 but only has cash. The customer agrees to not receiving the change, the employee takes the $20 and pays the $19.50 on his credit card. Also the store does allow for tips, that clearly is policy.
My question is, can management or a coworker demand that a staff member not do this? Can an employee be reprehended or fired for taking cash and then paying with his personal credit card? Would it make a difference if it was exact change?
The customer could turn to the next person in line, gives them the cash and gets them to pay on their card. Since this would be allowed, could the employee argue they are not acting on behalf of the company and just wanted to do a person a favour?