How is this not unlawful search?

I understand that because the use of and purchase/sharing of this kind of data (which for the purposes of my arguments includes any data broker data, including the data from Flock license plate readers) is not considered illegal due to a lack of consumer protection laws. But how is the government acquiring and using this data not considered a subversion of due process?

“The records contained passengers' names, credit card numbers used to buy tickets, departure and arrival cities, flight dates and numbers, and the agency responsible for the sale.“

And it includes flights that are totally outside the US.

A good reason to not use your primary credit card as who knows who has access to this data. A debit card linked to a burner savings account is probably best.