While I'd write the GM, speaking only for myself I'd probably leave off HQ unless the GM came back w/ an unsatisfactory response. Sounds like this was just a kitchen employee who was overzealous/anal in her interpretation of the rules.

And FWIW again speaking only for myself - if I had already grabbed a danish & tea & she wanted it back, I'd politely tell her to go pound sand.

OVMV. Cheers.