I get where you're coming from, but my experience is that even many people making sites for fun stick ads on the site in the hopes of getting a bit of extra cas

I get where you're coming from, but my experience is that even many people making sites for fun stick ads on the site in the hopes of getting a bit of extra cash. Lots of fansites did so in the olden days, and many useful sites, wikis and blogs do so now, especially if they either use hosting that adds them or they get enough traffic they feel they need to.