Yes so I can measure myself easier / better.

One of the reasons I like to play MMO's is because you get better, your ilvl goes up and I always strive to become a better player, increase my skill, part of that is also increasing the amount of damage I deal regardless the fact that I'm a tank, we deal damage too and I always strive to take the maximum out of it.
At least we have ACT but an official in-game parser would be easier (and maybe more accurate), like there's not really an open API where the addons can take info from (which is also the reason why there are basically no addons for this game)?

I don't really see why this is a problem, is there something wrong with me for liking to improve myself and like having a number to show my DPS and how much it goes higher as my ilvl and my skill to play the job better improves?