Sleepy,
Even where I live I have to go 20 miles to the nearest station that sells diesel whereas there are 5 stations within 5 miles that sell gas. 20 miles means I burn 4 gallons of diesel driving there and back home to fill up the tank in the truck. Go along highway 395 in eastern California and most of the towns do not have diesel. We have to fillup when we may have half a tank of fuel in the towns where there is diesel so we can make it the rest of the way.
Three out of four gas stations in California, Washington, Oregon, Nevada, Utah, and Arizona do not pump diesel. More than half the time I am buying fuel at a truck stop and that means traveling along the major interstates.
Easy enough to go to gasbuddy.com and for any trip from one town to the next check out how many sell diesel and where you have to drive to get fuel and how far off your route you have to travel.
There is also the pain of negotiating through the diesel truck stops and having to go inside with a credit card each time, which is not great with a camper but would be a major pain pulling a trailer.
The point is that there is no substantial benefit to having the diesel engine in a truck that will have at most a 6,000 lb. load. It is like the guys and gals with their Hummers and Land Rovers that they use to go to work and shopping - not much need for that locking differential and not much point to a 10 MPG vehicle for that type of use.