Po, os sabres refletem os tiros de blasters. Eu achava que era basicamente por isso, aí dei uma googlada e gostei dessa resposta aqui:
"Jedi are protectors and defenders, and the Way of the Jedi is the way of peace. While a gun is an effective weapon for defense, it really shines on the attack.
A lightsaber, on the other hand, is a perfect defensive weapon and a moderate-to-poor assault weapon. If you are ten meters from a Jedi armed with a lightsaber, you are relatively safe from attack...unless you start shooting. A lightsaber is literally incapable of firing the first shot, but just as literally able to return fire. If you get hit by a blaster bolt while fighting a Jedi, it probably came from your own blaster.
This actually makes the lightsaber a weapon of humility, limiting the sorts of things a Jedi can do. A mugger or a cop can completely command you from 20-30 meters, and a sniper can deny you access to an entire open area.
Finally, the lightsaber makes it easy to disengage from a standoff. If a shooter and a Jedi are in a standoff situation, either one can back up with both weapons trained until the shooter feels safe enough to put down the blaster. The Jedi has limited options for attacking a non-firing shooter at range: either throwing the lightsaber (which leaves the Jedi open for a blaster counterattack) or using Force abilities unrelated to the lightsaber. Once the shooter holsters the blaster, the Jedi can safely disengage their own weapon. As we see in the real world and/or modern-day stories, a gun vs. gun standoff is much harder to negotiate: the shooter who puts the gun down first is at a tremendous disadvantage.
All in all, using a lightsaber instead of a blaster makes a Jedi a low-level threat before you start a fight, and a high-level threat during the fight. This helps defuse situations before they start, convincing would-be assailants that they will live a little longer if they give peace a chance."