I disagree on the argument that all airsoft guns should be made of clear plastic (or something like that)
Indeed there have been instances of people getting shot for waving around airsoft guns like idiots when what they should have done was to keep their guns in a bag nondiscreetly, and only use them on private property. This kind of behavior only ruins the sport for the rest of us. (I admit that I am biased, being a former airsoft player myself)
In most serious airsoft groups, the rules are very clear. You are to treat your gun as if it were real steel, you will not brandish it outside of the playing area, it must not be loaded until the game begins, eye protection (preferably full face) must be wore at all times...
If you brandish a fake looking gun at the police, you might get shot. There used to be criminals who would paint their guns orange to make them look fake, but since fake-looking guns can look real and real-looking guns can be fake, you shouldn't take a chance.
I don't think it's a problem with the airsoft guns themselves. Besides, many airsoft players chose to start playing airsoft because they liked the relative realism (as opposed to paintball) so having guns that look like they come out of Toys R Us is kind of disheartening.