I have never said no to guests having people over during the day, but my city limits the number of people allowed. I do however agree with muddy that additional guests, even if they don’t sleep over, are a lot to expect of a rental - and it’s actually somewhat abusive of the hospitality. It’s a bit stressful to give people access to your home and trust them in your investment, but when they use it as a daytime crash pad, it’s not very respectful and it always left me feeling uncomfortable.
I will say, the majority of the guests I hosted pulled stuff like that unexpectedly. It didn’t matter if it was a group of young people, a couple of older folks, or a professional couple, they always seemed to have some other friends in town and they would want to hang around the rental during the day using the pool and whatnot, completely oblivious to the liability it put on me. Some even had children that didn’t swim running around the pool. People have zero respect or consideration, they only care about their own immediate needs. Never think otherwise.
Thankfully, I haven’t had to deal with anyone lately. I think you kind of have to separate yourself from what you think is right, and what you want/expect, and just let people take advantage if you’re going to short term rent your place. In some ways, I think a property manager might have worked better for me, let them handle it. That way I can detach from the drama - and there was always abuse happening. I don’t miss dealing with the crappy people. The few good ones I do miss.