It's sometimes the only way you get to communicate with all of the team during the week. So it's more of a social ritual than anything else and those are important too.

One way to avoid burnout is to achieve progress in the form of milestones.

Another one is the pure joy from achieving a difficult goal, e.g. a difficult problem that has eluded you for some time.

Those two things are what I am for to avoid burnout. And if there is no longer joy from the second option, then it might be time to call it quits.