Though I suppose if you're too lazy to just shoot their npc's...
Although I could see this command being useful for setting other people hostile to a faction.
Say /set [player name] hostile [faction]
If given to a select few people in official factions they could set certain people hostile to them
Use?
All the unaffiliated mercs that are shooting lawlful or unlawful pilots while maintaining their neutrality. They could change it so they are no longer simply neutral.