My name is Stuart. When I speak my name, I make a conscious effort to pronounce it clearly. I give the S plenty of hiss and both Ts have a strong snap to them. Yet for some reason, when I order my burritos, the folks behind the counter have difficulty with my name. Now don't jump to any conclusions about the people behind the cash register. They're all nice, hard-working people from a variety of ethnic backgrounds. Still, when faced with the prospect of typing "Stuart" (I accept "Stewart" as phonetically indistinguishable), they routinely fail. Comically.
My favorite bungled version is "Storch." Regrettably, I lost that receipt.