staffs can moderate the market
It is a free market that is fair to anyone
It won't be free or fair to anyone, at least not for long. If there is centralization, there will be discrimination.
For example what are you going to do when some government contacted you and demanded that you censor your marketplace for certain people, maybe they are coming from a sanctioned country or a country that the said government is at some silly trade war with?
That are some good points.
The first way to prevent discrimination the vendors won't get a username,
they get a 18 hex digits long username: 38e1236d4b389f7c75 or 0x38e1236d4b389f7c75
The only way is a short link like
https://example.com/vendorSimply disallow anything outside the market community forum,
add a random ID for every post and user and no users can be discriminate.
The staffs / admins need to add the idea except it is a idea like risking user
privacy or something that is risking users security etc.
The first way to hide the market is TOR, the second is to rotate the host services/server.