How can people actually loot luggage or critical components from air craft crash sites?

What kind of people could even do this? If I had survived a plane crash, or came upon one and saw people looting, i would take a stick or something solid and start hitting people over the head when I saw them.

People have either died or are in need of medical attention or just help to escape. And yet they ignore all of that and start grabbing parts or things from scattered luggage. 

Then there is the reward offered if looters or thieves return crucial parts or evidence. They should make the offer, but have a police or military personnel with them while they wait for people to come in (face it, these people are thieves so it’s warranted in my opinion) and once the person arrives they should confiscate the part and instead of giving them the reward they came for, have them detained or arrested. That way they can’t warn anyone else that they shouldn’t try to get the reward. After everything Is recovered or most of what is needed, let them go, or stay in prison/jail/detention. 

In a documentary I saw, someone referred to the person who returned the FDR for a reward as “a good guy”. Good guy? Who in hell could ever think that? They are pieces of ****. They have stolen something. They offer no help to those in need of it. They only cared about what they might be able to take. They only wanted to claim a reward for their stolen items. So... good guy? No.... piece of ****