Where were we again?, err, oh, right! Yes, Sci-Fi and blasters are an important part of the storyline (ref. the dark ending). Thus, at least if you play the light side, you have every reason to rid the world of those dreadful weapons. I usually collect every single blaster and blaster rifle and make sure I dispose of them properly, so that they cannot be used for evil again.

The easiest way is to ditch them out at sea, however, in theory, they could be found sometime, by smeone. You can stuff them down the Mt. Thunderfist volcano, although from the volcano you can actually recover them I you decide to. I suppose telekinesis might recover them if you drop them in the lava rivers inside Mt. Thunderfist, but when I do that or drop them in the volcano, I consider them melted anyway.

The point is that you can make it your mission to remove the blasters from the game. You don`t just choose not to use them, you actively put them where you cannot recover them and make it a quest you must do before you complete the game.