Checking out a customer's firearm and having a conversation about it is not in your job description is it?
Probably not, unless he's in the sales department, which he may be because he mentioned having a desk. If he's in sales anything goes that makes the sale, is cost effective from the resources (including his time) basis, and isn't illegal. My point is (and I'm also a business owner) that there MAY be some gray area here. I would be very hesitant to stifle a salesman that was producing for me.
Don't get me wrong, the ones fixing the cars... But, my experience in the auto repair business is that they are paid on a commission. So again, as long as the guy was/is producing I'd probably let it slide no matter what he did that didn't put me in a situation of being legally liable for anything.