Owning 900 domains hoping for them to be rented is "rent-seeking"
A simple test:
Would all of FolioHD's domains being rented benefit their business or not?
They are subsidizing the cost of buying those 900 domains into their overall pricing as a line item.
Now the registrar is trying to push out squatters. Sounds like the housing and renting markets. Insert surprise Pikachu face.