Be warned, this is likely controversial.
As a guest, I've taken to sleeping on top of the bed covers or on the sofa, in my sleeping bag. The reason being to save the host the trouble of changing the sheets. I do ask in advance if this is ok.
As a host, would you be appreciative, insulted, amused, concerned about the state of my bag, or the state of my mind? Maybe all of the above.
As a guest, is this something you'd even consider?