It's not only Airbnb in Europe, but also Erasmus (twice a year they make finding housing very difficult), Uniplaces (like Airbnb but for EU students), local classifieds sites (which now just double as Airbnb and Uniplaces listings) and being known as an affordable city (like here, in Lisbon, which is being called "the new Berlin" as well as the new "startup capital city").
Over the past 3 years, rental prices here have increased 30%, pushing locals out of the city center. A quick look on Airbnb for Lisbon, one sees the average monthly price at around 700 euro (for a room) while some listings go well above 1,000 euro. Three years ago, the norm for a room - no matter how you found it - was 180 to 220 euro per month, now the minimum is 300 and increasing. People are mad, and rightly so since minimum wage here is 530 euro.
If anyone wishes to see all the stats well laid out, this article below (in Portuguese) has been circulating locally. I suggest running it through an online translator. It's titled "Who is going to be able to live in Lisbon?"
http://www.buala.org/pt/cidade/quem-vai-poder-morar-em-lisbo...?
One of the images from the article is this (http://i.imgur.com/FFDVm0M.jpg) showing local Airbnb saturation, where 75% of listings are entire homes/apts. Airbnb's regional head says in 2015 there were 12K homes listed in the Greater Lisbon area, a 60% jump from 2014 numbers. We're a small city but data shows there are 174 hostels and 184 hotels here, with many more in the pipeline.
It's out of hand and the govt hasn't done much of anything to stop it. By the way, that local listing at over 1K euro per month? It had lots of reviews, meaning there have been plenty of takers.