Some moderators have public personas which are valuable to a community, have built up trust, have specific hard to find skills, contribute valuable content, etc

Some moderators have public personas which are valuable to a community, have built up trust, have specific hard to find skills, contribute valuable content, etc. If a moderator (or set of moderators) are able and willing to move a community, the market price of their work is the greater of what Reddit is willing to pay them and how much revenue they can receive from moving their community and capitalizing on it themselves.