In Ins2, they served a purpose. They could allow someone to sit back and support by softening up an enemy wave. There were better guns, and better sniper rifles even, but bolt-actions were viable.
Fast forward to Sandstorm, and they're worthless in every sense of the word. The semi-autos are better in literally every category, and they don't gimp you with a ridiculously low fire rate and horrible post-movement accuracy. On top of that, the bolt action doesn't even always 1-shot someone if you hit them center-mass! And if they have heavy armor, you might as well ignore them.
I'm not suggesting we go to Call of Duty jumping 360 no-scope levels of crazy. But it'd be nice if the bolt-action rifles had a place in this game that wasn't already fulfilled better by another gun.