Where did you get the '6-8 cases per week' from?
The approvals you see here or Rupnet are not the only cases they have approved! You also need to look at the number of cases being transferred or RFE-ed. They also need to attend meetings/trainings, read email and understand the ever-changing 'directives' from the HQ.
After all they are only human beings - so yeah, let them enjoy the long weekend.