Most of us place some sort of value on interacting with our coworkers about stuff that has nothing to do with work. Sure, there are employers who try to discourage all socializing during the workday. But they're in the minority today, because trying to police that behavior extensively does more harm than good for workplace camaraderie and productivity.
Some employers, on the other hand, like to market their workplace culture in their job postings. A culture that says "We're laid back" or "We're a fun place to work" is also one that sees value in socializing among its workers, and it can be a strong selling point when you're looking for a job.
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