Yes you're right, I'd actually forgotten they used to do that, I suppose the arguement is that the player wasn't sent off in the game, so the opposing team didn't get the advantage they should have got, or if the player got sent off but shouldn't have then the team don't get to play the game again.
But this is the point, we were in a quite normal position where human error was accepted as part and parcel of the game, but now we're in a postion where human error is still happening but is alot more difficult for people to accept, but this also comes with all obvious downsides it is having on watching the game.