I find it interesting that you name a number of concerns regarding nutrition, and professionalism.

Why is it that these concerns only come out when a parent is trying to justify a refund or stiffing the provider/babysitter out of her owed fee?

I had something very similar happen to me recently, these parents were all to happy to be in my care, but when I enforced my contract, they were all of a sudden wondering about outdoor time, said I fed their child junk, that they did not know that my husband was his alternate etc. (It is made very clear that my husband is very much a part of my daycare)

Interesting that these concerns were never voiced until they were trying to justify pulling their children without notice....

Yep OP seems legit to me. (Please note sarcasm)