Maybe I mis-read your post, I thought you were charging the surcharge for staying only one night (instead of two or more), but since this thread is about extra people, maybe you were charging for the extra people?.
Booked two nights, reserved the room for two people. Tried having a party in the room, until I called them on it. But had two extra people sleep on the daybed. Found that I wasn't stupid enough to leave linens for it, but still slept. Slunk out of the house just after check-out. Told XPDA story and had them marked as persona nograta. Idiots who don't know the difference between a hotel and a B&B and that I'm around all the damn time!
.