(USA, pre-pandemic) I've seen "mandatory" hand sanitizer use exactly once, at a camp which had some nasty norovirus outbreaks (which was misery, especially I'm sure for people who had to fight over shared bathrooms).
Now I see it at the entrance of most businesses / by checkout registers.
In a small sampling of places I've been in the MD metro DC area it's not uncommon they have a dispenser at the door, prominently placed to indicate suggested use. A few places have personnel dispensing it, some in a manner that does not suggest it being optional.
In the major metropolitan area in Germany where I live, I've seen this only once at a hairdresser last summer. None of the grocery stores I've been to has required this (though many now offer it)
Now I see it at the entrance of most businesses / by checkout registers.