The solution is the same as it is for so many other issues: strict liability for Airbnb. If the company is responsible for finding you a hotel room of equivalent capacity and paying for any difference in price, the company will quickly devote resources to minimizing this kind of fraud.
As long as it's not Airbnb's problem, Airbnb isn't going to solve it.
As long as it's not Airbnb's problem, Airbnb isn't going to solve it.