Again, I see your point, but I think in this specific case the added fun to the game FAR outweighs the problem of using a mechanic that's not beneficial to anyone. Simply put, while you are not really advancing the game by denying a creep, the ability to do so...
It's one of those things that's personal preference for me. I will never find stalemate mechanics fun. You can tout their strategic/tactical importance to me for hours and hours, but the final result is that I will still find them fundamentally boring.
It's like trying to convince someone who doesn't like the color orange that they should wear orange shirts.
You're going to have strategic/tactical decisions happening whether this mechanic exists or not. There is no denial mechanic in LoL, even though I play support role for the carry quite often, I still find myself constantly busy. I don't just stand there doing nothing, I'm putting down wards for vision, watching for enemy movements on the map, using my positioning to try and zone the enemy carry/support (either out of position to prevent them from last hitting/harassing my carry or so that we can jump them and score a kill).
Just because a mechanic isn't present doesn't mean that the game suddenly becomes empty, other things are taking place and things still happen.