I just decided to try out the throwing spear and I didn"t like it (I prefer guns)
but I did notice something weird when I used it I thought i heard the grenade pin sound when I used them

has anyone else noticed this or do my ears deceive me?

Yeah I think they just reused the sound

If you look at what you're doing in third person you're actually throwing the spear up, catching it, then throwing it.

It looks like they used the "pin sound" sound effect for that animation

Pretty much the grenade animation, I never noticed the sound though.

Spears are good with Heave Ho! and Poisons. The little animation before throwing is the only thing that annoys me.

Now if only you could actually buy them somewhere, and re-use them.....