Well, before all the a-holes come in and say "you should feel guilty about taking advantage of this...you should flail yourself with a rope w/embedded razor blades....." I want to say:
Congrats! They messed up. You caught it. There is no moral quandry. You didn't kill anyone. You're not taking the food off anyone's table, etc, etc. Enjoy. Just don't register the darn thing!