Things I Don't Get (II): Remastering Music

I know the answer to the following question is "corporate greed preying on ignorant consumers", and that I'm naive to believe record companies actually care about what they contribute culturally and historically, but still...

...why in the blue hell do we need a remastered version of a Maroon 5 album that came out 3 years ago, yet Husker Du's Zen Arcade can remain left alone without any remastering?