I have never had anything of the kind happen to me in any hotel (Hilton or otherwise) - care to share the hotel name?

Process wise, a reservation on a credit card is not a final booking, it must be reconfirmed to become one, it may be released (normally when checking out), or if nothing is done it will lapse - my presumption is that in this case the hotel did not make a reservation, but an outright booking, which they subsequently refunded.