[grzm]

You'd be surprised how often people do in fact do exactly that. I know two personally. I don't have overall figures but it's definitely greater than zero.

Isn't there a service which shows popularity of search terms? That would be one way to get a handle on frequency.

Found it:

https://www.google.com/trends/explore?q=Facebook

I don't know this tool well enough to know if this is for queries where the only term is Facebook. Happy to be corrected!