Should it come to a real court, though, I imagine AirBnB would say something like "we're basically a common carrier, so we're not on the hook, and you can't compel people to house everybody in their own domicile, so even if they are racists there's nothing you can do about it". Rather like Uber trying to have their cake and eat it too.
Uber is a service that abstracts the drivers. AirBnB is a marketplace where the seller is clearly identified, sets their own prices and policies, has their own reputation, etc. They are very much not alike.
(This is not a endorsement of their arbitration policies, mind you)
I don't think they can claim common carrier if they're involved to this level, can they?
But I don't see why giving price suggestions means they are suddenly responsible for the policies of their users.
In other words, greed. That's all it is