When you eat animals you give the market a financial incentive to breed and slaughter more animals, who inevitably have to eat a bunch of plants to grow. It’s not that you eating a burger kills a cow, but you eating a burger helps make it financially sound and socially acceptable to murder cows for burgers.
The problem isn’t that AirBnB gets a cut, the problem is that they make such a process more efficient and accessible. Property is a finite resource, especially when talking about a specific area like a city. We don’t want to turn cities into amusement parks that the workers have to commute an hour to get to, even if that’s what is the most profitable. Housing should be affordable and available for the people who actually use and make the city run daily.