jeez - I was trying to give a few suggestions to "sell it" to mum so to speak. Of course it is nowt like real one but a bit better than trying to practice with a Nerf
Chock makes excellent points, what would they consider "not realistic"? or acceptable? I'd rather have my teenage son airsofting than playing a video game any day of the week!
Just admit to them that they're right, and that with all the money you'll save not airsofting; you'll be able to afford that drug habit you've always wanted.
You could always point out to them that there has never been a single instance ever, of anyone going into a school with an airsoft gun and killing dozens of their classmates and teachers and then turning the airsoft gun on themselves and checking out. And that's because they are not realistic.
Then the problem is easily solved; challenge them to a duel to settle the matter; pistols at dawn. If they don't like pointing guns at people, your victory is assured.