score:7
I found some answers at their website at How to check in for a flight?:
They only have self-service kiosks in Riga:
Currently available to our passengers travelling from Riga airport, self-check-in kiosks allow you to check in at the airport free of charge.
Also, they do have a 10 EUR airport check-in fee, but that does not apply to "passengers who have already checked in online, via mobile check-in or at a self service check-in kiosk".
They confirmed on Twitter that they'll print it for free as long as you have checked in online:
Hello! Weβre sorry for late response. If you've checked in online, you can get a boarding pass at the check-in desk free of charge.
Anyway, it looks like their mobile check-in is a better option if you happen to be in possession of a mobile phone, as you avoid queuing at the check-in desk:
A: With airBaltic mobile check-in you will save time and money, escape queues and the EUR 10 check-in fee at the airport. It gives you flexibility and the possibility to check in on your way to the airport. Please pay attention to the check-in deadline.
You enter booking ref and surname (whether or not you've already done online check-in) and get a "mobile boarding pass" with QR code to show at the gate:
Edit: Last weekend I used the mobile boarding pass on four separate airBaltic flights, so I can confirm that there is no need to print anything by yourself.