Well, you don't need to pay anyone to do encryption. You do need to do pay people to do identity verification. That's a more-than-pedantic difference, even though encryption without identity verification is generally meaningless.
First off, you're already paying someone to have a domain name. I sorta understand the distaste on principle, but I've never really understood, as a practical matter, why paying $10+/year for a domain name is totally fine, but paying $5/year on top of that for SSL isn't. (And yes, the race-to-the-bottom has hit $5, see ssls.com. This isn't even counting StartCom and the future Let's Encrypt.)
Second, and related to that, what you're paying them for is the human element in key continuity. If you ever lose your key, you're going to want to be able to regain a key for the same website that you've already published everywhere, that everyone already has localStorage for, etc. And be careful about saying that you don't care: Crypto.cat (which, at this point, definitely knows what they're doing) managed to lock themselves out from SSL by requesting a hardcoded public-key pin and then losing all the public keys they'd pinned. This isn't really a risk that you think is realistic until disaster strikes, and the last thing you want in the middle of a disaster is to have to rename your website and convince everyone that they should use the new site.
And the process of maintaining infrastructure to re-provision certificates to people costs money. It's possible that it could be funded in different ways (just like, e.g., all of the work that goes into the browsers themselves is funded in ways that don't involve charging website owners or users). But there is a thing there that involves humans, there are advantages to it involving humans, and humans need to be paid.