Pronouncing local place names. Lots of scattered areas here with place names that are spelled like other places names (for example we got a town called Egypt, a town called Binghamton, etc.) except that they're all pronounced differently. For example, we have a town called Leicester, named after the actual Leicester, and locals tend to raise an eyebrow when someone asks "how do you get to lester" (that would be the normal way to pronounce it)?
"Who's Lester? Is he the new guy in town?"
"What? No, the town."
"That's Leesester, not Lester."
"I'm sorry, wut?"
I of course just add to the confusion if I'm the one to break the news, as I have a Kiwi accent, which is atypical around here. So it becomes a "what do you know" kind of interaction.