Yes, that was actually what snagged me on the HND-TPE flight. Taiwan's regulations said that the passport had to be valid six months or you needed a visa. I had neither, and wasn't allowed to board.

With all of these situations remember: If the airline doesn't check it is much worse for the passenger. No one should be contemplating the likelihood of getting past a check in agent. They should be contemplating the likelihood of getting past an immigration official at the country they're going to. And that likelihood is low, no matter what happens with the check-in agent.