She’s been doing the heavy lifting of daily child care for years – which can be exhausting, isolating, exhilarating and boring. (All in one morning!) Let her have this. And let her know that it will be a good thing if it makes her happy, even if she never makes much of a profit. Now, can you bring yourself to believe that?
So be the backbone here. But don’t try to create a sting operation – it shouldn’t be your job to police her. Plus, she’s obviously quite practiced in evasion. If you can’t find it within yourself to pick a private time to confront her, then leave her an anonymous note that says, “I’ve noticed that you’ve made a habit of not paying at the cafeteria. Please stop, as it is stealing from our company.”