Itâs apparent the world is getting used to staying in strangers' homes. It took four years for Airbnb to get to one million guests and now, in the past two years alone, Airbnb has seen roughly 30 million guests and has over one million listings globally. At the heart of this campaign is Ellie, who in a letter to her Airbnb host lays out the emotional journey of her travels, from addressing her friendsâ concerns about her staying with strangers, to the delight she experienced throughout her trave...