I'd consider south america as part of the west. I'm from Brazil and I'd never just pop in a friend's house without being invited over. I suppose if you live in a small town that could happen. But I do think americans do that in small towns too.
Before the smart phone I think it was less odd to pop in if you were in the area, but with phones, I feel like anywhere I lived people would at the very least send a message.
Before the smart phone I think it was less odd to pop in if you were in the area, but with phones, I feel like anywhere I lived people would at the very least send a message.