I agree.. If anything, a list (or more specifically), Evidence, that something is being done will only encourage people to use the report feature, and scare of the kids with an urge to destroy people's games, cause lets face it, they are out there.
I don't see how this could be a problem ? Openly announcing the banned accounts, not with a reason why, just a list of the names of the accounts.
It's the same with a lottery, if people keeps on playing but never hears of anyone winning, they become rather suspecting. Whereas, if a winner is announced (perhaps even with an interview) people know it's not a hoax (or in this case publicity stunt) and they will reccommend the lottery to their friends etc.
Here it would make people take the report feature seriously, knowing that by being a flaming rtard in a game can have consequences for you later on.