Earlier quoted context omitted.
You will usually see these in public places that have no other access controls - think in a park, rather than in a restaurant. It's for places that have a high risk of people sleeping in them.
Yeah, I do visit public bathrooms from time to time, especially in Spain, Germany, France, Denmark and Sweden, and never seen that once anywhere, although I've seen much worse things on single occasions than a timer for the door to open.
I've seen them in some of the shadier parks in the Netherlands, Italy and Austria. Yppenplatz, Vienna, has a particularly nasty (smelling) one which the countdown clock does very little to obviate.