They've never made much money, with relatively slim operating income margins.
Yet they managed to sell for 300 times 2014 earnings (with the first two quarters of 2015 being negative on net income). That's an extraordinary multiple to say the least.
They managed to sell themselves for what they might have potentially been worth ten years from now, if you priced them similar to how the market prices Expedia or Priceline. That's assuming the competition doesn't gradually erode them of course.