[QUOTE=reubenT;8167796]
If I don’t want to keep a given horse, why restrict what someone else may want to do with it? [/QUOTE]
I know someone who was so appalled by a breed registry/actions of local individuals involved in that registry that she decided to sell the horse as grade rather than risk the horse ever being shown on the breed circuit.
As others have mentioned, papers are sometimes withheld on TBs to prevent them ever racing again.
All this is different than the person attempting to extort extra money for the papers, but sometimes people look around at the world and decide that being grade may not be the worst thing that can happen to a horse.