Those dents look a little small for a BB gun... not to mention that anything more than 1-4 pumps would probably tear right through a zincoln. Still, that's some amazing marksmanship if that is from a BB gun!
Wouldn't surprise me, given the amount of abuse they seem to get. Back at my old job, the cashiers would get shifts in the liquor store where we'd get hours of down time in a stretch and nobody checked the security cameras as long as the tills or inventory didn't come up short. I came in once and the guy on the morning shift had clipped all of the pennies in the "Take a penny" jar in half with bolt cutters. Something about bored 18-25 year olds with no supervision and access to tools...