in my opinion importers and pet shops bring in fish for different reasons, they think it will sell or it has been ordered and then not picked up etc,
if no one buys a potentially big fish from the shop and they can't house it long term then it will be put down or maybe given away.
some shops don't inform people or they don't know themselves
personally i think giving a fish a home for awhile is better than no home at all and a death at a young age.
the ones you need to be rarking up are the importers not fellow forum members,