Out of interest, where were they from? Could have been a dialectal thing. For example Inverness in Scotland is right on the border between the Gaelic speaking parts of Scotland, and the English speaking parts. So it acts as an isogloss between both of them. So they hybridise pronunciations in some words. An example of that is the word sight, which a lot of Invernesians would pronounce as shite because si is a sh sound in Gaelic. If the customer were from such an area, it is possible that that is just how they pronounce the word Asian. You also need to remember that due to the diversity of languages and dialects, there isn't really such a thing as pronouncing a word properly (to an extent of course).

Man, get over yourself OP. F your life over someone mispronouncing something in front of you? EGADS. Maybe this is more of a first world problem than an FML. My step day always says EYE-TAL-IAN instead of Italian. I'm not about to go complain about it.

Sounds like something I'd do if the other words were difficult to say.

Just say it correct when reading the order back.