Surely they could be fooled into taking a fly other plankton feeders are ! Mullet, milkfish, etc. Imitate algae.
The commercial exploitation and finding a market for them is all , as the man said, about perception. Market them with an attractive name .Start with low prices , get celebrity cooks involved, overseas food programmes ? etc. etc . It's not rocket science .
They sell spur DOGFISH here in the UK as " Rock salmon" . What do you prefer ? How about "Riversteak"
Only a matter of time.