On the streets of NYC, I don't really notice the cigarettes, but I do notice the enormous amount of plastic bags (much of it stuck in trees), plastic or paper cups, straws, takeout containers. And gum. If you ever look at a sidewalk and see dark splotches [1], that's discarded chewing gum. It's absolutely everywhere. Not as invasive, of course, just odd.
I don't know what SF is like, but NYC has a fascinatingly ugly system [2] where you're supposed to put trash and recycling out on the sidewalk for it to be collected, where it's effectively temporary litter. NYC's sanitation workers are notoriously careless about handling the trash, and my pet theory is that a sizable portion of street litter actually originates in the sanitation workers spilling trash on pickup day.
NYC's trash problem is also exacerbated by the fact that landlords can get away with not doing their part in keeping the outside of the building litter-free.
[1] https://www.ediblegeography.com/wp-content/uploads/2011/07/S...