I don't usually mind song remakes since it's nothing like remaking a movie, that's whole big ordeal all together. Song remakes are not often anyway, and sometimes it's usually much older songs like from the 80's or something.
Like how Disturbed did Tears for Fears song "Shout" or the Ataris remaking "Boys of summer" from....I don't know
. I think the only real reason the songs were remade were simply to add to the whole publicity of the movie's release.
Movies don't get jammed back into theaters with 3D effects after years of DVD shelf life around their belts. My guess is remaking the 4 songs was a means to attract popuarlity and just a means of getting more money out of the film.
Considering that I just download music anyways and not buy CDs that often, it's not a problem I really worry about since I know I can get it for free without feeling ripped off. But remakes are either absolutely amazing or totally craptacular.
It's all in the matter of what you like as far as taste goes in the end.