That's a bad comparison. Marriot is hugely leveraged [1] on purpose (tax shield reasons, etc. etc.), while Airbnb isn't.

It would be better to compare the firm values instead of equity values (which you can change in one day just by issuing debt and using the proceeds in a share repurchase)

[1] http://marketrealist.com/2014/10/why-ev-ebitdar-multiple-bes... Apparently they do a trick to put most of their debt off the balance sheet, through lease obligations. Thus, if you just do a quick glance at their numbers, they appear to have a low leverage.