Maybe there could be some kind of alert system in place when a PC, be he a trader, explorer etc, comes across someone with a Wanted tag of some significance, could relay the sighting to the local authorities, which could then be intercepted by bounty hunters?
You could be in SC, see a ship, and if you target it, ID it and it comes back Wanted £150,000! and you were not in an Anarchy system, it could automatically relay that to the authorities, or maybe have to be manually done by the player.
It makes larger bounty fiends have to be careful of contact they want to avoid, kind of like how the general public help with sightings of known criminals on the run.