Let's see now. Handling a loaded weapon in the store, muzzle not pointed in a safe direction, finger on the trigger? Evidently didn't know what he was doing and proceeded anyway. Accident waiting to happen maybe but definitely not an accident. Negligent discharge and endangering the public in my opinion. Not to mention stupid! He needs to be fined, put on probation and find another line of work.
yeah accidents happen, but this is ridiculous for a number of factors(some mentioned by you). It is good the victim seems to be in a situation where he can get thru this. He'll probably have a lot going thru his mind this Thanksgiving.....