If you bought a membership that allows you to bring a guest, then you should never feel guilty for taking advantage of the benefit you paid for. As I understand it, the guidelines do not say you have to be friends with the person you guest into the club.
And you are NOT responsible for making their business a "Profit Center".
You did a good deed and should feel good about that.
Now, if you took $40 from the person... that would be a different issue!
HHHHmmm... now THAT could be a personal profit center!