A drone costs more than a helicopter. The FAA has ensured that the price isn't going to fall too far since their avionics has to be DO-178B class A rated. I.E. the same rating that passenger aircraft need to get.
So long as there's significant penalty to participating as a seller in this market for those actually writing the software then I don't see why it can't be public. I don't think it would be a good idea to allow without penalty someone who is writing the software to be cashing in on million+ dollar bonuses for back doors he writes himself however. That seems analogous to insider trading.
Forfeiture of all money gained as such and a stiff jail sentence should be enough to discourage any but those who are already doing this without public knowledge of the market.
That's _expensive_