Spears are just daggers with too much handle.
Here are a couple of reasons not to include them - all that reach is like an "I win" button for melee combat. And that goes both ways. Imagine an enemy poking you with a spear and you can't get close enough to hit back. Annoying.
I think you mean
awesome...?
some NPCs would be badass enough to still take you down with their sword even if you had a spear.
The PC would also be able to take people down who had a spear - if they were good enough. (magic, bows, etc)
Spearmen and pikeman existed in real battles and still got killed, so whats wrong with having it in a game?