It's definitely not cheaper than using free fonts. Or even modifying an existing one -- it's not as if Airbnb's exclusive use of this font is going to benefit them in any measurable way. Even if that were necessary, it seems like they should have just paid Netflix to use their font, and maybe make some changes, rather than working with Dalton Maag to make damn near the same thing.
I don't know the details of Linotype GmbH's licensing agreements, but my point was that this route is surely less expensive than commissioning a new font.
Can it? How many people-hours went into this, and which fonts have higher licensing costs than that?