Were you on the illusion that they didn't have your biometric data? Or that they didn't have the passenger list with your name in it? Those two are pretty transparent (and honestly, not a big deal).
Does biometric here mean your passport photo? I totally believe this is the official name, but the nomenclature definitely opens up the possibility of concept creep so that biometric data can mean anything from the mundane to the terrifying
A set of high quality photos, from a few different angles, a set of fingerprints, and quite possibly a sample of your writing gait. Also, very likely, some measurement of your height.