This TP discussion has gotten lengthier than I thought ...
I've noticed that some hotels start one out with what appears to be a full roll. However, in case of distress, there is a partial one available as well.
On a related note, I use sealable small plastic bags to bring home the used soap bar. Throwing one away is a waste; yes, I can afford my own. I've heard some hotels have dispensers - I'd be for that.