Charity isn't earned, charity is given. People are giving to Chris because the empathize with his plight and are concerned for his well being. Whether Chris knows it or not (and god-bear help him, he probably doesn't) this may be the first time in his life people have seen him as a human being first and autistic man-child second. Well, except for when Bob died. It's too bad that the only time people feel for him is when something tragic happens.
The people who are giving money know the risks. It's unknown how Chris will use the money. Given their current situation, I have a feeling that most of it will be put to good use. Will some of it be spent on pointless shit? Probably, especially once their basic needs are met. The thing is, Chris is now in a position where he's going to suffer a lot if he blows what little money he's getting on video games. For the first time in his life he's going to be faced with an adult decision: do I want to have fun or do I want to eat and stay warm?
I also find it hard to blame Chris if he does end up spending some of the money on something he finds comforting rather than what he needs to survive. He's just been through a very traumatic experience, especially for someone with autism, and I can completely understand why he would want to distract himself from that. Assuming Barb isn't in control of Chris' finances at this point, it's up to him to make the right decision, and the real world will reward or punish him based on what he decides.
pickle donations gladly accepted 
