I lived in Taipei for a couple of years. The "third space" is super common there. People would hang out at coffee shops (loads and loads of coffee shops), get "afternoon tea" with friends, or go to a park or even a subway station lobby and socialize.
The Taipei metro even embraced it and set up specific places / spaces for shopping or socializing (that were dual purpose rather than simply being a corridor).
I feel like this is missing in the US, and genuinely miss wandering around with my backpack for a Saturday. It was a load of fun to head out for an early lunch, go find some random coffee shop to "work" (aka "surf the web and people watch"), then find a place for a beverage and maybe go see a movie or have dinner. Those days were genuinely the most fulfilling, especially when I'd run into random acquaintances.
Bringing it back, a river runs through downtown Austin with a great hike / bike trial along it. There aren't really many cafes (I can think of one) along about 10 miles of trail that are good "destinations" to wander toward while enjoying the scenery.