Because no other game has them?
Hard to implement properly?
They just don't like spears?
Just to piss you off?
Spears are overrated?
Because casual players hate spears?
Because of consoles?
Because they're superfluous?
...
1: Morrowind, mount and blade
2: no not really see morrowind and mount and blade
3: why they are an amazing weapon
4: probably trolling the core users
5: no they arent
6: probably
8: most likely
9: not really
Spears if done right (see Mount and Blade) are amazing at what they do;
1: if we had mounted combat Spear/pike=win
2: if we had npcs who knew how to fight instead of charge charge charge then spears are a great support weapon, because if the enemy is a bit far off for your sword bro then you poke him with your spear making him close in to attack you thats when your sword bro comes in.
3: great in hallways trying to keep enemies off of you
4: would be perfect vs dragons and other large beasts
Also with spears you also have halberbs, pikes, awlpikes, and poleaxes ect ect ect ect.
http://www.youtube.com/watch?feature=player_detailpage&v=NqC_squo6X4#t=2194s