The companies are too hard on their employees so you can't blame them for trying to rush around and get their job done. No excuse for some of the bad things they do though.
My mate used to work for a delivery company and he said he used to arrive in the morning to a big pile of his parcels in the depot and he had to sort through them all and put them in order, load them in the van and plan his route out before starting his deliveries. Then you have traffic to contend with, I'd hate to do their job.