Other departments do not have minimum staffing levels, if people are sick or leave is not covered you have no option but to adapt and work harder, why is this concept alien to some CC?
CAA regulations say that we must have a minimum crewing level equal to one crew member per 50 passengers so that everyone can be evacuated in an emergency. Not a random number but one that has been arrived at after extensive testing with a variety of different aircraft. The CAA are not interested in how many crew it takes to serve coffee, (in fact they don't care whether you get a coffee or not) they are just interested in safe operation.
I guess most other office/terminal based departments rarely have a decompression, NITS (planned emergency)briefing, evacuation, etc so no-one notices if half of them are off sick or on leave. In the last six months we have had two full evacuations (a 747 and a 757), and six NITS briefing on Eurofleet alone.
Hope that explains why the concept is both alien and undesirable.