Whither the B-sides?

In the past, I've generally thought of B-side songs to be more throwaway songs that weren't good enough to make the initial cut. Yet on a few albums I've listened to more recently, I'd argue that the B-sides were probably better than most of the songs that hit the final track listing. This seems to be a particularly acute case with AFI - a band that I've generally felt has tried a little too hard since they hit the mainstream with Sing the Sorrow. On that album, both 'Now the World' and 'Synesthesia' were better than almost everything on the album (save for perhaps '...but home is nowhere' and the title track). Subsequently, 'Rabbits are Roadkill' and their cover of NIN's 'Head Like A Hole' easily outpaced everything on decemberunderground, which was a mediocre outing at best. On their latest, Crash Love, the music is definitely improved, but nothing is particularly memorable. Yet, as I hit their first B-side, 'Fainting Spells', it sticks with me more than any of the songs on the retail track listing.

I'm not in the music industry, but if you have some kick-ass songs, shouldn't they be going on the CD that most everyone's going to be listening to? Same thing goes for Rise Against, a band I have a notably higher opinion of these days. 'Historia Calamitatum' and 'Elective Amnesia' wipe the floor with most of what comprises Appeal to Reason.