Because their (or their friend's) computer can't run the anticheat, but they're interested in playing with friends? My sister and mom wanted me to play Valorant with them a free years back, but apparently it needs kernel anticheat, so I just can't run it. I'm not going to buy a new computer for a game.
And the way community policing worked in the past is that the "police" (refs) could just kick or ban you. They don't need a trial system if the community doesn't want that.