As the title says: how often do you reuse your towels? I stayed at an AirBnB in the East of France this summer and was given two towels per person for a week. I also stayed at an AirBnB in Northern Italy and was given two towels per person for ten days. I personally think that's not enough, especially in hot weather when I take daily showers. When I'm at home I use my towel once and take a clean one for my next shower.
Edit: the towels on holiday were also a lot larger than the ones I have at home (50×100 cm)