I used Airbnb recently and I had a larger unit than would be available at a hotel with my own kitchen and fridge and the cost was less than 50% of the hotel cost.  I was in town for four nights, so the saving was significant.
Forget all of the rhetoric about "fair" - this is about money.  The city gets a lot of money from the hotel industry and it gets nothing from Airbnb rentals - that is the problem