I've wondered if it would make sense for hotel/motel chains to offer a paid toilet service. Their locations already have a bunch of toilets (one in each guest room plus ones for the lobby and for meeting rooms) and already have cleaning people there to keep those clean.

Sell day passes that give you 24 hours access. If I were, say, going to drive from Seattle to Los Angeles I'd pay $20 to buy a pass that would let me pull into any Motel 6 along the way to use a clean bathroom.