is there any explanation why most of all the mp3 players out there dont come with belt clips? I know some come with armbands and others you have to buy them separately--so I ask again why not belt clips?

Couldn't tell you, as mine came with one.

because belt clips are for nerds?

Well, if it's an Hard Drive based player belt clips are a terrible idea as you get a ton of vibration around the waste. There's much less vibration on the upper arm when running etc. (though I still personally advise against using HD players for workouts).

Flash players are so small you really don't need a belt clip. Just stick them in your pocket if you don't want to use the arm band.

Plus, as dick-grayson said, belt clips are nerdy.

Just put them in your fanny pack.

nerdy or not--it should be optional.

It's supply and demand. They aren't going to waste their money packing in an accessory that most people have no use for.

And assuming you can buy one on your own for your model, they are optional.

My dell came w/ a case w/ a belt clip.