Why are there so many Walgreens in San Francisco?

Profit. If you want to sell something, open shop where there are a lot of people. If you want to sell a lot of something, open shop where there are a lot of people prone to buying your stuff. read more

In San Francisco, Chicago, and Minneapolis, there's about 1 Walgreens per 14,000 people. Las Vegas has about twice that density, one Walgreens per 7,500 people, even if you include 100,000 tourists / day. Source: white page searches for # Walgreens in various cities, divided by population. read more

Then, in the Western Addition, there are many smaller street level gangs, with one notable gang called the "Eddy RoCC" gang. The gang controls most of the inner city projects by putting kids as young as 12 on the street corners selling drugs instead of going to school. read more