Its all about layoffs.
Pension contributions are only made on the first 8 hrs worked. Lay a driver off and the company contributes nothing to his pension, everyone else maxes out at 8 hrs regardless.
Sick days are accrued based upon hours worked....but only up to 6 days per year. Lay a driver off and he isnt accruing into his sick bank, everyone else maxes out at 6 per year regardless. Same deal with vacation accrual.
Health benefits only kick in after 40 hrs per month. In my local, the company pays about $1000 per month for all eligible FT employees. Lay a driver off and he isnt costing the company a grand, instead he drops into the hub and onto the cheaper company plan and displaces a part-timer. Its one less benefit package to pay.
I'm not 100% sure about this but I think that workman's comp rates are also based upon the number of FT employees rather than the number of hours they work. Lay a driver off and you arent paying for his comp insurance.
UPS pays to insure its package car fleet. Right now we have about 20 cars "mothballed", they are not in service and therefore not being insured. And if one route is eliminated from a loop, the overall miles driven by the cars in the entire loop decreases because there is one less vehicle accumulating mileage to drive to and from the area.
There are probably more savings that I'm not even thinking of. What I do know for certain...is that somewhere, in a dark little room with no air in it, there is an anally retentive tightwad with coke-bottle glasses sitting in front of a computer who has calculated this all out down to the gnat's ass and determined that the aforementioned savings outweigh the additional overtime costs. What was not factored in....was the poorer service, increased injuries, and loss of morale that results when routes get chopped. Those are someone elses problems.