Toi and apy are correct that this is a case of zeh nehneh vzeh lo chaser and is entirely mutter (assuming the OP would not have bought a room through the caterer in any circumstance.)
DY, ZNVZLC may be a ptur and not always be a heter but that is more relevant to a case where a person is actually using someone else’s property. In this case the OP is not even using the caterer’s property!