more than anything, this seems like a feeble attempt at a rich person to do something they consider "crazy" so they can have a cool story to tell their friends over caviar. "oh wow, look how dirty i was! ha ha!" this guy needs to get over himself.
there's lots of reasons why people become homeless (http://en.wikipedia.org/wiki/Homelessness#Contributing_cause...) and most well-off people simply don't think about the kind of problems people have to deal with just to survive. homelessness is a multi-faceted and complex issue which encompasses millions of people in different situations. there is no way to "see how they live", unless maybe you got some head trauma, a broken leg, asthma and were dumped somewhere you didn't know with no support system and no job skills (compounded perhaps by a self-medicating drug or alcohol habit).
do you want to help the homeless? tell your congressmen to pass laws that help them with their real life problems they need to overcome (http://en.wikipedia.org/wiki/Homelessness#Problems_faced_by_...) before they can try to sustain themselves with a job and housing. donate to organizations which provide food and shelter to many instead of handing out money to individuals. give old clothes and supplies (like the backpack & sleeping bag he tossed) to goodwill or a local shelter. mainly the way people can help the homeless is by putting forth resources to help people learn how to elevate themselves above simply surviving, which most people eventually settle for compared to what seems like the immense difficulty of getting a stable job.