Not everybody does that, though.
That's a big deal with "consumer" series computers. Consumer series computers are loaded with crap. Literally.
Vendors like Dell and HP get paid by companies to bundle software on their machines. You end up with dozens of programs you would have never bought in the first place installed on your computer. I don't mean the helpful little things like Dell QuickSet power management or the CD burning software that your CD burner wouldn't work without.
I mean things like MusicMatch Jukebox (does anybody use MusicMatch these days?), MyWay Search Assistant and three different online-service trial offers.
Who needs that crap?
This guy named Jason York decided enough was enough, and created a little script called The Dell De-Crapifier. It's a simple script that un-installs a lot of the junk that came pre-installed on your Dell (if you're not like me and you just start using your computer when you get it). It's not flawless, it doesn't have training wheels, but it's something to help the folks who don't spend all their time installing operating systems.