It might be interesting to research why self-identified middle/upper class people paid less attention to strangers when they knew they were being recorded. or perhaps why self identified lower class people paid more attention.
For myself, I find that this sort of giving is really just about me. Sure the person might be a scammer or drug addict or whatever. But I'd rather be the sort of person who cheerfully takes a chance on helping someone, and isn't all uptight about a few dollars here and there.
"some of the biggest names in tech" turned out to be three. And big is a bit subjective. I never heard of "Om Malik, a partner at True Ventures and the founder of tech site GigaOm" before, and I only know the third guy since he is the Craig in Craig's list.
Not much of a surprise, we see this sort of thing with any widely reported issue with a specific product. History is rife with examples of mass hysteria, combined with users/owners trying to blame their mistakes on the manufacturer.