For one, dresses are way overpriced:
Yglesias, who is getting married this month, sympathizes:
We don't drive great bargains on wedding-related things because we don't want to see ourselves and be seen by others as being stingy about such an important event. So if you're purchasing wedding-related items in a marketplace where everyone else is also shopping for a wedding you're looking at an environment where the prices are systematically higher. By contrast, if you shop in a normal store then even if you, personally, are acting in a relatively price-insensitive way the fact that everyone else is driving a harder bargain helps you out. If you're determined to be traditional, there's no way around this but the price you pay for self-selecting into a niche market is pretty high no matter what strategy you adopt.