There was a youth shotgun for sale and after I checked it out I told him to put it up to his shoulder and see what he thinks. Keeping his finger off the trigger, and pointing it in a direction away from others he put it up to his shoulder a couple times. Right away, the worker comes over and says "he cannot hold the gun because he's not of age."
Is this a state or federal law? Or just this stores policy?

(Just to add, I'm being a bit vague about the store. It's not Walmart, which I had him handle the Cricket with no problems).