I have a friend who moved to the US from India. He says when he first got here he was frequently bumping into people in hallways and sidewalks, because his instinct was to move to the left, and as he eventually figured out, the US instinct was to move to the right.

The only reason we could come up with was driving sides and the India/British left side vs. US right side. Because he wasn’t constantly bumping into people in India, lol.