Actually I agree you were a bit extreme there Maiden. Airsoft guns are definitely toys, and most can barely shoot their little plastic ball across a room in a straight line. Although there are some stronger ones. I own some, and have shot people and been shot at- some of the "really nice" ones can sting, but in no way are hurtful...
I don't know about the laws in your area, but in mine- if a cat is a a problem on your property, you can catch them and send them off to the pound where they are held for a period of time for the owner to come get them, or they are adopted... Unless they are unadoptable, then of course that bad thing happens. I would definitely prefer that if it were my cat in someone's yard that didn't want it there... they would use some type of scare tactic that will not harm the animal to help deter it from visiting that area.
I feel like the misunderstanding of what an airsoft gun is (probably assuming it is a BB/Pellet gun) is where this came from, hopefully the clarification of it helps put all at ease. Feel free to PM me if any of you have more to say, this thread will be "cleaned" in the near future. =)
Andrew