Joke right, why do you care that much, multiplayer achievements suck but you cannot deny they keep people playing multiplayer, Iv earned them all legit (kinda, boosted a few in reach but earned them after anyway)
Yeah they suck but they are staying around.
Not a joke, my wallet's my only option in terms of getting my (tiny) voice heard, and I've been using it all generation. If I don't like a certain aspect of the game that could have been easily avoided (day 1 DLC for example), I don't buy the game. For Halo, since I can't not buy it, I'll just buy it used.
And no, achievements aren't what keeps people playing Multiplayer (except for Seriously type achievements, which are the only ones I wouldn't have minded in Halo but aren't there). The LW achievements from H3, or the Living Dead achievements in Reach are certainly not what's keeping me on Halo.
Good gameplay should keep people playing your game, and achievements are there to reward you for playing. You're not supposed to count on fucked up achievements that will take ages to get until you finally get lucky to keep your population levels high.