Yes, there are lots and lots of people who don't wash their hands with any regularity and others who don't wash them as often as they should. You can find statistics about the fraction of folks washing hands in a public restroom, or just watch for yourself the next time you're in a public restaurant or buying food from a restaurant with an open kitchen.

Then advocate for it with a valid reason?

There seem to be plenty of diseases that are commonly spread by inadequately washed hands. COVID does not appear to be one of them.