Many registrars operate as brokers for domain sales indeed (i.e. godaddy, namecheap). Then you have tlds operators with their "premium" domains that go for 1000x the regular price. Premium usually being defined as the top 10k english words and every kind of l33t spelling of sexual words.

Neither registrars nor tld operators care about squatting, even when they don't get a cut. Why would they? The squatter is paying them the same as you'd pay them.