I guess it depends on which coins you are comparing and where (as in country) you are buying. A quick look at Aust, Canadian and USA sites shows Eagles appear to have a small premium compared to Kooks, Maples, Philharmonics and Kruggerands. Maples are within the price range of the other government issued coins. Sometimes Eagles are cheaper than Kooks.
Basically, all buyers can suffer from irrational thoughts. If a silver coin is bullion why should any one coin be valued more than another? The only difference are the pictures stamped on the coin. People buy what they like. People will pay a premium for a coin of a certain year or for country of origin. In the end (for me at least) bullion is bullion. Buying cheap means buying more. No commercial buyer is likely to pay a premium for an Eagle, metal is metal. YMMV.