@ Wakizashi: Perhaps I may see where you're coming from, if you're referring to a certain kind of homeless people. Because I see some of those as well, and wonder what's their problem. I'm talking about relatively young people, in their late twenties or early thirties, most of them better dressed than I am (not kidding), smoking a cigarette and drinking a cup of coffee, and begging for money "for a cup of coffee".
With respect to those people, yes, I am "wtf ?!". Dude, I couldn't afford smoking if I was a smoker, and I definitely don't spend money every day on coffee... And I would gladly give them my sandwich (whenever I had one), if they were asking for food... but when they're explicitly asking for "coffee money"...

If that's the case, and it's this kind of people you were referring to, then I see your point; however, I hope you're aware that not all of them are like this, and some of them are really in trouble, and it's not "by choice". The "American Dream" is just that, a dream - it's not achievable by everybody. We don't all start equal, or are given equal opportunities through life. Yes, I am aware some overcome their problems and rise above the average, but there are also those who start well, but fall down below the average.

I have admiration and respect for those who DO manage to work their way out of poverty and such, but it's by no means a rule - rather an exception, and, while it does indeed depend much on one's abilities and willingness to make an effort, fate/luck/opportunities/environment play a significant part as well.