"AirBnb increasing rents" is theory popularized by hotel industry and never been confirmed with hard data. AirBnb allows anyone to profit from demand for lodging, as opposed to few large hotel chains taking all profit. For many AirBnb hosts it's their livelihood. E.g. do you see benefit in anyone being able to start a restaurant or do you think only large restaurant chains should be able to do it? Also AirBnb increases tourist traffic benefiting other businesses.