You need to think about the team you want to have in the future, not just the team you have now. You might currently have three guys who are all in their 20s, but you don't want to lock yourself into a culture that would make it hard to later hire a more diverse group of more experienced people that a growing company may require.
For example, a 40 year old female marketing director isn't likely to be interested in hanging out with 25 year old guys after work, so if you make that kind of forced socializing an official thing organized by management, you'll run into problems.
For example, a 40 year old female marketing director isn't likely to be interested in hanging out with 25 year old guys after work, so if you make that kind of forced socializing an official thing organized by management, you'll run into problems.