I go out to cafes half of the time - even if it's just 4 hours or so. That said, it's relatively easy/quick for me as I live in downtown San Diego. There's literally 5 cafes within a 2 block radius of my condo and probably a couple dozen that are great for working out of within a 5 mile drive. I'm not super social but I regularly strike up conversations and occasionally form friendships while I'm out and about.