I'm going to take one more shot at explaining my rationale regarding a pickup bed. All my truck is used for is to tow a 5th wheel RV. The pickup bed is purely cosmetic insofar as my application is concerned. It's much more economical and practical for Dodge to supply a pickup bed for the 4500 off the lot than for me to have to buy the truck and then go to (an extreme example) B&W and have an Elite-series towing bed installed that's going to cost another $8K and, because of its weight, chew into the GVWR and GCWR ratings of the truck. The pickup bed also allows the truck to be parked in many deed-restricted communities (such as mine) and keeps the truck off the scales in many states.
If that doesn't work for your application, that's fine - you can buy a bare bones C&C and set it up any way you like. For many (most?) RV and "horsey" trailer pullers in my situation, however, the 4500 with a pickup bed would be the preferred solution for the reasons cited above.
Rusty