Yeah, if I'm going to be honest, if you can't afford $100/yr you can't afford to host, so you're not going to be a contributor to their community. Looks like the filter is working.
I used to be very active on Couchsurfing and have hosted dozens of travelers -- to rave reviews, and much more often than I stayed. It doesn't cost me anything to share a couch (or a room, on the rare occasion I had a spare). What I'm objecting to is the website taking $100/yr -- for what? It's unclear -- on principle, when communities like it have existed for far cheaper and far longer. It seems to exploit both the hosts and the guests. I understand some overhead (especially when it comes to trust and safety) but it's not clear to me why that price point is necessary when alternatives can offer the same service for much less.
[0] Yes, okay, fine, the marginal cost is not truly, literally zero: there'll be a few cents for water, a little wear and tear on the equipment, a few squares of toilet paper, a couple squirts of soap, etc. However, most people do not track their budgets that closely anyway, so it would be lost in the noise.
So the fee is really only if you want to be a guest. But then you need to host to earn credits to be a guest.