Yes, companies have ways to do this with a decent amount of precision and accuracy based on existing user behaviors. They can often even be detailed enough to know that LTV differs depending on the channel that the customer was acquired by (e.g. organic vs. Facebook ads vs. search ads) and tailor their ad spend accordingly.

I don't know what AirBnB's numbers are, companies aren't required to disclose this and they guard it very closely :)