Europeans thinking a 2h trip is a long ass trip. Then they come visit North America thinking they can visit from coast to coast by car in two weeks.
North Americans going to Europe thinking it'll take 4 hours to go from one city to the next when they can actually cross three whole countries in that time frame.
The most culture shock I've ever experienced was being in southern France, craving some Italian, and realizing I can literally just go to Italy for dinner.
I think the cultural influences from Mexico should count. As far as food goes, Mexican food is some amazing stuff, but the American variations are different, yet amazing in their own rights. Tex-Mex, New Mexican, and Cali-Mex are some of my favorite spins on traditional Mexican food. Plus I think you're already including Mexican influences with BBQ and rodeo.