Although, on Apple's support website, it says that that iTunes backups that happen automatically DON'T backup songs, photos, etc.
What seems to be happening is that people keep the songs they import to iTunes on iTunes. I don't (didn't) have the space to keep 3514 songs on my computer. I would keep all the purchased songs from the iTunes Store, but as I would import my CDs, I would put them onto my iPod, then delete them from my iTunes library. This backup system on iTunes is for the people who keep all the songs in their library after importing them. This is because the backups only save settings and things of no importance to me that can easily be replaced. Songs cannot be easily replaced. Do I have to buy a backup program that I will only use once, or am I completely wrong and I shouldn't have to worry about this?