This is a wrong assumption. I took my six-year-old daughter to the Civic Center in San Francisco a few weeks ago. There were thousands of people on the streets and all of them were doing drugs, passed out from drugs, or high on drugs. One guy was passed out on a major street and cars were driving around him. Another guy comes up to my daughter and tells her 'don't do drugs because you will end up like this'. There are parts of San Francisco that are a complete dystopia. I simply cannot take my daughter into San Francisco anymore.
Instead of helping these people with mental health and social programs, they just give them tents and section off streets so they can camp outside. This is true in many other cities in the U.S..