An earlier post referred to transhipping being a "labour-intensive" operation and thus, by implication, one that the companies would seek to avoid.
We are used now to the fact that the cost of people is the most expensive component in many industrial processes. One of the biggest societal changes of the last century and a half is that, certainly prior to the second world war, labour was incredibly cheap and machinery relatively expensive. When you could get labourers to do grunt work for pennies there wasn't much incentive to invest in expensive machinery: labour-intensive is preferable to capital-intensive. Hence the persistence in the traditional steam-age transport systems of what look to us now like incredibly inefficient methods of working - hand-operated machinery, multiple manual handling of goods, masses of porters on stations, locomotives which require armies of back-up staff to operate, manually operated signalling from closely-spaced boxes each of which has to be staffed.
After the second world war, when the price of labour rose exponentially, the incentive to mechanise and simplify also rose. The labour-intensive nature of the steam-era railway is what gives models of that railway their enhanced play-value (sorry, "operational potential"), but in real life that came at the price of mass exploitation of working people on poverty wages.