Yanbu op. I think everywhere should be obliged to let people use the toilet.
I've had ibs issues, to the extent that I had to plan my entire route and know where there were toilets and easy places to park, for every journey I made. My need to go became a bit psychosomatic, made worse when there were no toilets. I used to have to start dosing up on immodium from the night before if going somewhere out of the ordinary.
I remember going in a fish and chip shop with restaurant attached to ask if I could use their loo. They said no, use the public booth down the road.
In normal circumstances that would have been fine but I wouldn't have made it and didn't have the specific change and wasn't capable of all that fucking about. Asking for change, getting to the toilet, messing about putting the money in, avoiding the hepatitis or whatever the fuck else.
All because an empty restaurant wouldn't let me use their loo. The thing is, I'd have bought something after, and I offered this but they still wouldn't let me.
How someone can refuse a desperatly sweating person the loo, I don't know.
The co-op opposite let me use theirs in the end. Where I bought something after too.
Basically, I think it should be illegal not to have accessible toilets.