They give away paid products for free. Products that Google penalizes you for not having. Then, many people needing or wanting that product used their free alternative.
I still don’t know if that vs version with more paying customers is a good thing in long run. Good for now, though.
In practice, most CAs are over-charging for what should be highly automated (like LE). Other CAs also push EV and other certs that cost more, but don't really add much value in practice.
In the end, the "free" version is good enough for most people. I would suggest if you're using it in a commercial environment that you consider setting up a scheduled donation. Which likely does help a lot for what they are doing.
I still don’t know if that vs version with more paying customers is a good thing in long run. Good for now, though.