As far as I know, most RV manufacturers do not deal direct because most of the factories don't have the personnel available for final prep and for the customer walk through. They also don't want to be bothered with time-consuming price negotiations. There are some exceptions of high-end, custom RV manufacturers; but as far as I know, most RV manufacturers sell only through dealers.
At the Hershey show, there will be factory reps available, but the manufacturer will be assisted at the show by a dealer. Some of the dealers are located as far away as New Your and Ohio. The factory reps answer questions, but any selling that is done is done by the representing dealer. You will take delivery of the RV, whether bought off the floor or custom ordered at the show, at the representing dealer.