Actually, legally, they sort of have to give up the data. They are taking a risk not handing over the data, thankfully it's the right risk to take. The law is malleable for a reason; laws often become outdated.
Business wise they should to do this, yes, but that still doesn't mean it's an easy "they sort of have to" situation.
Oh, I definitely think that they'll have to give up the data eventually, but considering that their business model is at stake, they have to at least try to hold out.
I'm not a proponent of AirBnB's business model, but I can understand their attempt a refusal.
The fight is more important than the outcome, in some ways. It will be interesting to see how they play the PR/legal/international angles to get at least decent results in NY.
Business wise they should to do this, yes, but that still doesn't mean it's an easy "they sort of have to" situation.