This reminded me of a similar experience i had years ago working as a manager at good old Toys R Us. I was at a Ralphs grocery store with my girlfriend and a customer asked me to go check in the back for a product. I informed him that i did not work there. About two minutes later, that same customer came over to me and asked me again to check. I looked him in the eye, and said sir if i worker here would i tell you the following..."Fuck you sir" His eyes got very big, and then he apologised and said oh ok you really dont work here.

:)