I was recently in Copenhagen (one week, lived around King's New Square), and to be honest, I don't think I even saw any junkies there. Much less any obvious homeless people. Rode the subway every day, didn't see anyone there either.
It was pretty much the polar opposite experience of walking down any major street in LA or SF. Of all the metro areas I've visited in Europe, Copenhagen had the least visible amount of junkies and homeless people. I've been in Oslo tons of times, and there you see them quite frequently (but compared to California they're pretty much non-existent)
Try exploring less reputable parts of town, and not tourist trap areas. While SF has problems, others have some too. You probably just stuck in wealthy tourist areas, which they would probably police more to keep people coming and spending money.
It was pretty much the polar opposite experience of walking down any major street in LA or SF. Of all the metro areas I've visited in Europe, Copenhagen had the least visible amount of junkies and homeless people. I've been in Oslo tons of times, and there you see them quite frequently (but compared to California they're pretty much non-existent)