I am friendly with my coworkers and might occasionally spend time with them outside of work, but, for the most part, all my closest friendships are not from work and not in the same profession (outside of the few I picked up in school).
To contrast, I have some philosopher friends and they discuss about food (they, unlike me, love cooking shows), travelling, but also philosophy. There is never any feeling of "this is work, we don't talk about this". It's very refereshing. And I imagine writers talk a bit about writing too.
This does not fit my experience. It's rather that many passionate programmers are rather eager to talk about what they do at work (at least if they are allowed to), but the common situation is that what they do at work is barely interesting to people who are not at least somewhat interested in programming topics.