If everyone behaves themselves then it really shouldn't be a problem. Of course the hotel staff know exactly what is going on but providing no complaints are made then they really don't care. The issue of towels never seems to be a major problem, they just nick more from the trolley, as smiths points out.
It's a big if though.
Sergei's group of bored prossies are likely to get themselves noticed, as is Sergei himself as he loiters around on his mobile and that won't be good for non-sex related hotel business. Punters can also be complete idiots. I had waited for some time for a certain prossie to tour her way back to Cambridge, made a booking and half way to the hotel got a text canceling. When I did meet her a week or so later it turned out that earlier that day some twat of a punter had decided the best way to get her room number was to walk up to reception and ask for Tight Sofia. He then created a scene when he was told to sod off and a result she was asked to leave. I don't have any reason to disbelieve the story, in fact I can believe that some punters really are that stupid.
The best hotels for punting don't have card access, parking limits or barriers to the car park which make punters desperate who are desperate for a shag and who are inclined to moments of idiocy do stupid things that draw attention and raise complaints.
As I just posted on another thread, there seems to be a move from hotels to working flats in the Cambs area and I think certain hotels have experienced a considerable drop in revenue as a result.