Ups saves money by violating the contract and hope that they dont get called on it.
At what cost? Would you have a problem with them busting your route out and sending you home, while they pay a ptime air driver $10 an hour to do it?
Of course I would. I am simply saying that perhaps they can justify violating the contract and paying the grievances if doing so allows them to make service or pull a feeder on time or whatever may be needed to ensure the operation runs smoothly. Maybe the cost associated with the grievance would be less than the cost associated with service delays/failures which would result in service refunds. And, as you stated, not all contract violations result in a grievance being filed, so that is why I stated that perhaps they think that contract violations are simply part of the cost of doing business.