Pirates can be pirates all day long. There is thousands of NPC traders that they can pirate from.
Bountyhunters understood that concept. Most of them are NOT after other players, but after NPC pirates, getting bounty from them.
Player pirates are in nearly all cases only after other players, and not because they want to be pirates but because they just wanna have an excuse to kill other players.
If pirates, like bountyhunters, understood what their JOB is (pirate EVERYONE, not only players) theyd be making craploads of money.
Craploads of money you say?
Well i flew a cobra with 36 ton cargo, a default sortie yielded about 35-60k credits and took more than 15 minutes.
You call that money?
A single python bounty is about 40k and takes about 2 minutes to claim (given you use ammo weapons like missiles).
The problem is with piracy, you got to be lucky to get the big bucks,
from rare cargo or highly priced goods, which is 10% of all sorties.
There is no money making in NPC piracy, that is why player piracy is a necessary thing,
stealing rares and selling them is worth the effort.