Yep, also some airdrop of some altcoins. These data is really important to these kind of projects. Most of those email addresses and some information are for sure interested in cryptocurrency or already involved with cryptocurrency.
The less worst will happen is some people may advertise ICO or some airdrop to data, and worst is to phish those people.

I hope this is the last incident for Ledger, for sure they may lost a ton of customers because of this breach.