An RV show, the larger ones anyway, are a good place to see a lot of models and get a feel for what is available that might suit your needs. As for bargains, probably not so much. The dealers usually have "show specials" that offer attractive looking discounts, but they are seldom more than an advertisement of the price they would have offered in their showroom anyway, once you began the bargaining process. 10-14% is a typical show discount offer, but you may well be able to negotiate 20-25%. For those who aren't inclined to bargain with dealers, the "show price" is a decent deal, but the savvy buyer can usually do much better. Sometimes you can win some better deals the last day of the show, if the dealer is anxious to gain some additional sales before going home.
However, smaller dealers seldom discount much above 15% anyway. You will likely have to go afield to find the deep discounts, which are typically found at higher volume dealers. If local service is important to you, bargain hard but accept what you can get at local dealers.
Unlike cars, RV dealers don't get monthly quota bonuses, holdbacks and things like that from the manufacturer, so they are working strictly from their wholesale price base. However, their mark-up is higher to begin with. On the downside, it may be difficult to determine the real MSRP becauese there is no federally-mandated window sticker and dealers often make up their own "retail price" to display. And some are prone to adding in the same sort of extra money-makers that car dealers like, e.g. paint protection packages, fees for doing the required pre-delivery prep and inspections, origination fees, etc., so watch out for them. They are not at all industry standard practice. The RV manufacturer expects the dealer to do a pre-delivery inspection with you and perform any necessary preparation as part of the dealers normal cost of doing business.