I agree with you, but, honestly, this one's on the devs, not the players. It's a pretty huge oversight to screw that bit of code up. Players will do it while it's there, and you can't stop the missions, short of removing all massacre/kill/scan missions period.
Personally, I don't care about the money, I just want the final 30% of my rank so I can buy a Corvette...
Z...
As I indicated in my other post here, learn how to control these systems, its actually very easy to shut down the missions, Change them to a different type, many players including myself do this all the time. And its not an oversight. This has been explained in numerous threads.
If you have 7 factions in a system all competing for control and in that there are pirates in system or a nearby system , the piracy affects there overall plans, if all 7 factions offer you 11.5mil to go kill 48 specific faction pirates and you accept such a mission, 1 from each of the 7 factions, it is only natural that killing those 48 pirates will get you paid from each of the 7 factions that you accepted a mission from...Bounty Hunting 101
And if you offer me this same contract several times and I accept, you then pay upon completion of said contract. The contracts themselves are not asking for names or scalps, only that you kill 48 of a specific faction...fairly simple and quite straight forward.
You want to change the mission types that are being offered, put the factions into boom, or famine, or outbreak, if that's not good enough, take their control away from them, defeat them and take their stations or put the stations in a different factions control, too many variations of this for me to bother to list here. Also a few options to actually stop the missions entirely...but you need to learn more about the game to apply these things. BGS....anyone can apply it anywhere, try it...