I look at dealer prices as "suggested" prices. Unless it's a highly desirable item that the dealer knows he'll get his asking price for, all others are open to being haggled over.
It's a mall and the overhead for dealers can be worse than ebay. I recently tried to rent a locked cabinet at a antique shop and it lasted for 3 months and all it did was cost me money. $60 a month may not sound like alot but when the PM percentage profits are minimal it ended costing me 35%. I must say that is a tough business to make money in unless you are the one who owns the joint and are colecting the rent from your tenants.
Usually a very large antique shop they also call them malls that probably has 200+ dealers all competing for your business. I live in a town that has about 10 antique shops and about another 50 within a 50 mile radius. There is also about another 10 that are just coins shops.
Although many antique mall coin shops do over charge, the one in my small town has competitive prices because it's competing with 2 coin shops in the area.