When you have thousands of people on the street in what is supposed to be one of the wealthiest cities in one of the wealthiest nations on earth, it's likely that the root cause is a societal problem.
I agree that everyone has personal responsibility, but the tone of your argument suggests that you believe most people on the street just consume narcotics and don't want to find work. That simply isn't the reality. Many of the people you find on the street led regular lives until a mistake or hardship pushed them down. Many want to find work but can't due to the difficulties associated with doing so once you don't have a home, even if you're already in a shelter. For those who are consumed by the struggles of addiction, we obviously haven't taken the correct course of action to address the issue.
I love my country, and I refuse to endorse any course of action that leaves another American behind.