Stops people from using meta to try and clear themselves (I'd never kill X, basically another form of cheating)
Stops experienced players from getting N1'ed 50% of the games.
Prevents a bunch of reports about grudgekilling, like this one https://epicmafia.com/report/207332 Mods already can't handle the current reports so taking work away from them is always a good thing.
Arguments against:
You can't get trolls out of your game. (Because for some reason, being able to kick people from your game is not possible)
None of the n1 actions affect the game as much as a kill, I've never seen a report for someone getting grudgehooked every game or grudgeinvestigated. But you're right, making everything random would be great.