Rarely do I end a multiplayer session considering where I could otherwise have spent the time, though I often question the investment after playing a game alone.
With Halo, where I interact with most of my online acquaintances, I dislike custom games, preferring to compete as a team, formally and seriously against strangers. Pickup games don't "count."
And, too, in team games I am compelled to keep the group coordinated by requesting updates on location and intention, and even issuing directives as politely as one can do with friends.
What that says about my E/I dichotomy, I don't know.