Devils advocate: you are getting access to a service that uses google's assistance for spam or abuse protection, not entirely unpaid.
No, the company that integrates it makes me pay (by doing work for google)
Either way, you train ai and watch ads in exchange for content.
Again, worthy trade off, not much of a work to solve one recaptcha, and the service that you use remains available more reliably by filtering out spam bots that could potentially render it out of service otherwise.