> I feel that once you attach a minimum wage then the Au Pair is now an employee.

The Au Pair was always an employee - whether you're paying them exploitative wages or not, they're still an employee.

>Do you need to pay minimum wage and still feed them the good food that the family is eating or you can feed them the cheaper employee food?

You never had to feed the Au Pair the same food as the rest of your family, it was just the decent thing to do. I really don't understand this concept where, just because you're no longer exploiting this employee, you now feel that that opens the door to questioning whether you should now be exploiting them as a person instead.