@Ann783 I think, for me, the biggest issue with the "visitors that aren't staying overnight" is the use of utilities and other amenities.
People visiting are plugging in devices, using the bathroom, consuming snack items offered for guests, and while it may not seem to be more laundry because nobody is "sleeping in a bed", someone might think it's perfectly fine to use the shower and a couple of bath towels, too.
Case in point, I had a guy book for himself as a place to crash for a local event. He was going to be flying out after that. On his last night, he mentioned that three of his friends were meeting him, and all were flying out together, and they just wanted to "be able to shower and change" before heading to the airport, but not sleeping over.
I told him that the additional per-guest fee was for use of all amenities, including shower and refreshments, whether or not the person occupied a bed for the night. He did pay up, and, as it turned out, their flight was cancelled due to weather, so they could only fly out next day, and they ended up spending the night after all.
My point being that, once a visitor is on the premises, one can assume they will feel like they can make use of all the amenities offered to guests, basically for free.