The correct word would have been more overt, not hiding at all. Compliance with DOT, FAA and TSA is a condition of carriage. Only have to do it you want a ticket.
Hidden behind that condition of carriage is all sorts of other "conditions" that we aren't told about and the reason we aren't told about them is because for the most part they are an unconstitutional search. Keeping what they found out about you so it can be used against you later at a time of their choosing (1/6/20) is the icing on the cake.
All of that data being collected by the private sector amounts to little more than an SQL database for the feds as well.
SCOTUS has ruled you have no expectation of privacy. Essentially they are saying you have no privacy other than the thoughts between your ears. That is all wrong. It's flat out RONG! too.