Why would you want an hour long track?...

Because some pieces of music are best when listened to as a single unit. Some rock operas, for example. Or Pink Floyd albums.

Until we can get gapless playback working perfectly, doing the "single track" trick is the best way to get things sounding perfect without a "blip" between songs.

Although doing it by recording through the PC's mixer is the wrong way to do it. An analog recording is never as good as a proper digital rip. If Musicmatch can't let you edit track start/end positions, then you should use a different piece of software to do the rip.