I went looking for a Canon 430EX flash unit. After pricing the item, I went to my local Samys brick and mortar store. I knew their in-store prices were probably higher than their online but I had no idea. Online price $240. In-store: $300. That's a 25% mark-up.
Even ordering from B&H with next day shipping, I'd probably save $40 over the in-store price (including taxes).
Seriously, why even bother having physical stores if there is such a financial disincentive to buying anything there? (Yes, I realize that some people like having the personal service, but that's a heck of a premium to pay for the privilege...)