Right - the noise has already happened, though.

To choose a more permanent example - property damage. If the tourist damages the property, you make the property owner pay for repairs. OK. Maybe AirBnB can help the property owner track down the tourist to get the money for repairs, maybe not. But the point is that the damage still happened in the first place - a longer term tenant that faces their neighbours every day would be far less likely to have done the damage in the first place.

But if you hold the tenant responsible for the actions of their subletters, then they'll be less likely to sublet their room (or at least be more discerning about who they let sublet); the end result is that the issue diminishes.

> Right - the noise has already happened, though.

Well, that's a physical limitation. Arrow of time and whatnot. It also applies to all penalties. Of course, the point of the penalty is not simply to raise money or get revenge after a rule is broken. The purpose is to disincentivize breaking the rule in the first place.

Fine the property owner either way. If the tenants were there with the property owner's permission, it's the property owner's responsibility.