Speaking as a US resident, it's not uncommon for me to hop on an HN thread and realize after a second that it's about a different country—India is very common, but also the UK and Canada and occasionally Germany. Sometimes it even takes a few minutes before that's clear. When that happens, sometimes I keep reading, sometimes I move on. What I don't do is leave comments about how irritated I am that someone had the temerity to start a conversation without making it clear in the title that it didn't apply to me.
