This was a fabricated example, actually: I work in tourism not in logistic (but I have friends in that field).

My point was that to the layman this does not make any sense while if you are managing a shipping company you soon realize that some destination are more profitable because your truck that was maybe taking specialized replacements parts from A to B can easily pick up some other stuff to send back to A, while travelling in the opposite direction your truck has a high chance to travel empty on retutning to base... but you still have to pay the drivers, the fuel, the maintenance and possibly tolls.