Yeah, sorry, I realized after I commented.

You know, I do not actually know that a website had ads before clicking on a link to it; I would be happy to only visit websites without ads.

It’s scummy to shove ads in my face without at least warning me and giving me a chance to leave, I think.

Of course there is a means to enforce payment, paywalls. Ads are a particular model for monetization, it does not mean it is the only one. How about when you want to see a movie, nobody will let you in unless you have bought a ticket. Now of course theaters know that you have paid, but they still say, hey, here are 30 minutes of ads to go with your movie, but then it is then fair for us to show up late.