But it may deliver that 3-4 hundredweight to several shops on that street, and several on the next, and ...
Goods are typically delivered on pallets,
Not actually the case for most local shops and stores, the majority of the deliveries are well below pallet size..... and unlesss every shop on the street sells the same item, it is highly unlikely that an articulated lorry would deliver to more than one shop on that street.... in fact it would be very uncommon for an artic to deliver to more than one shop in a town.
so either you need vehicles that can carry at least one pallet (which rules out any of the very small ones) or you need to account for the cost of breaking down the pallets into smaller units, which is time-consuming.
Costs that are incurred already in order to make the deliveries. For instance, we have an articulated lorry delivers bread to the local Co-operative they do not receive a large pallet of bread, they receive half a dozen baskets, to make that delivery the cost of breaking down a large consignment is incurred by both models, so it is a red herring to try and make it unique to smaller vehicles.....in fact may be additional as you would have to put the stuff on a pallet to use the articulated vehicle model in the first place, so the use of pallets is an additional cost.
I'm not against it in principle, but I'm unconvinced that all the smaller vehicles needed would be safer than one big one, and I think the costs would add up to a substantial amount - which would, of course, be passed on to customers.
Not at all, it is simply a model that uses appropriate vehicles for the requirements, and the costs may even be cheaper if you take the time, inconvenience and damage to the local environment into account