Culls will always have a home in the RAOK section too
Myself for example - I have two tanks and wanted shrimp in both. Don't want a breeding program and don't intend to cull anything or enforce any specific trait - just wanted a handful of rejects from people who are trying to do these things.
They end up with perfect Painted Fire Reds and CRS that are almost all white - I get nice 'just plain red' and CRS with bands of white and red, exactly what I wanted for 'pets'
Culls could also be used as feeders for fish, but I don't think anyone offering "culls from my breeding program for the cost of shipping" would ever have to wait long in the ROAK room!