This, right here, is why Silicon Valley has problems with diversity. As a rule of thumb, the only people who actually want to go to happy hour with their co-workers after 8+ hours of taxing mental work are 1) young 2) white and 3) extroverted. In other words, they fit the "brogrammer" stereotype. I've never really liked going out with my co-workers after work. When I'm done, I want to go home and decompress, not deal with another two or three hours of enforced social interaction.