What about considering both as parasites, just different methods for achieving basically the same thing: "More money for me".

Obviously, the landlords are the ones who raise the prices. But I think it'd be ignoring reality if you didn't consider the fact that AirBnb made all of this so much easier and simpler from the landlords. There are platforms that let you sync to many portals, and even see what weeks you should raise the prices to optimize for as much profit as possible. AirBnb and the other platforms are contributing to a constant, collaborative raise of prices.