Ya' know, what baffles me about this is that this thread began with an implied question "what deuce doesn't have these, I'll never know" - well, maybe the poster doesn't know - but I do, and several other people do, and this information has been published on this forum in the past, as well as in print. It is, as someone pointed out in this thread, simple economics.
However, in reality the question implied was a rhetorical one - that is, it appears the original poster, and some others, instead want to make a case that they are smarter/better automotive designers than were employed by Reo.
I am not saying that the G-742 are the ultimate off-road machine - they are not - nor were they built to be. These trucks in fact were a "interim" general purpose cargo truck design that managed to soldier on for 50 years.
Now, the Reo-design competed against a wholly different design put forward by Studebaker, as well as the GMC design (G-749) - and a Ford design that didn't leave the drawing board.
What all these designs had in common was that they tried to give the customer what was being ordered. That customer was the US Army - not the Russian Army, not the German Army, not some guy who wants a rock-crawler, not some guy who wants a mud buggy.
The guys designing trucks for the supplier's to the Russian Army, British Army, German Army were undoubtedly just as smart and talented as the fellows working for Reo. The guys in the design bureau's for Soviet Army, or the German Army, or TACOM are all also probably equally skilled.....but each had their own priorities in design, be it cargo capacity, weight, fording ability, cost, mobility - thus the specifications given to the truck manufacturer's varied.
Best wishes,
David Doyle