My question is, why do some low levels think they have all rights in the low roulette and to make players go slowly and loss his time? Don't they know that the low roulette is mostly intended to help newer players complete content? If they want exp, they could probably do FATE's on that extra time and get more exp.

Because, I mean..is the same. Why can anyone enforce what he wants to the others, no matter who they are?
That aside, I don't undertand why any lvl 50 do low level roulette. I only do it when I'm leveling a class. And even when I' leveling I want to do the dungeon as fast as possible. Why? Well. Multiple reasons. It's more efficient. It's more fun. You know how fun is doing Copperbell as a SCH? It is not fun at all. I can use "Follow" a rangued DPS and Eos will do all the work for me as long as I come near my mouse from time to time to move the camera. And in higher lvl dungeons it's almost de same..."almost".

That's why I prefer big pulls. And I prefer to skip trash mobs when we can cause if you're doing roulette you get more exp if you finish in less time. At least I think so. And anyway, exp/time will be better.
But of course I don't have the right do make people do as I say. And I shoudn't , that woudn't be fair. But of course I can leave if a dungeon that I think coud take 20 minutes to a good party is going to take 60 and I don't mind to take the penalty.