the delivery drivers are paid by the mile (one way) and not by the hour .... the bottom line is they really don't clear much money per trip so they have to make as many trips as possible .... that doesn't excuse exceeding the speed limit but it does provide a motivation .... they are liable for damage done while in transit .... I don't know if they would be held liable for a damage from a tire failure while .... I have seen campers with axles not properly aligned that literally wore the tires out while on the way from the factor to the dealership
Jim