Provide a persuasive argument as to whether or not gratuities of this nature should be acceptable

You are a rookie FBI special agent conducting field work alongside an older, experienced agent. You are working late into the evening conducting interviews. The experienced agent tells you that the restaurant on the corner likes to have armed law enforcement officers around because they deter crime, so the owner gives free meals to agents and police officers. Your partner mentions that he never used to eat there, but when the restaurant was robbed at gunpoint three times in 10 day, he now visits this establishment at least three times each week. (Note, armed robbery of a restaurant is not a federal crime.) He invites you to visit the restaurant with him tonight to introduce you to the owner…and eat.. He proceeds to order steak, potatoes, and all the trimmings. What are you going to do?
What if it were just a convenience store offering free coffee, and the owner refused to take your money at the cash register? (Note, the owner also provides coffee to the postal mail carrier, deliver drivers, etc.)
Provide a persuasive argument as to whether or not gratuities of this nature should be acceptable