In low level roulette and all other dungeons you gain exp for killing the trash mobs.
But if high level roulette or any of the more recent level 50 dungeons just before heavensward even as level 50 / 51 you gain no exp except for the roulette bonus and final kill.
Low level roulette with heavensward contains all dungeons upto 60. So please at least make it so that even a dungeons such as keeper of the lake or temple of quarn hm, etc you go in as a level 50 and not gain any exp for anything except for roulette bonus.... I am sure there would be a lot of players more willing to help random players maybe farm zenith more if at least at lvl 50 >54 ish you would gain some sort of exp or at least exp according to your level via high level roulette. It just seems like it might be some oversight but sure would be a nice small quality of life addition for people who still do them whether to help fc members, zeniths, or via roulette.