Am I allowed to stay with a relative or a friend when I visit their town? I am totally ignorant of local norms, maybe I should be in the Holiday Inn next door instead?
The line got blurry with the advent of the internet. How do you define "friend"? First there was craigslist and house swapping, and then there was couchsurfing.com, and then came Airbnb, which injected a giant pile of money into the system and everything went haywire from there.