I worked in the credit card industry for a stretch. Part of my job was to ensure adherence to federal privacy policies. So I'm well aware of both how data mining works and the federal limitations on such - there is a firewall between companies that mine the data and the credit card companies to prevent abuses - even though I worked for the bank in question, I could not legally see our customer data.
I see no such firewall when the feds get the entire Verizon file.
the government is engaging in far more intrusive data collection - to determine that people are buying cigarettes mail order to avoid taxation. getting credit card records, records from all the shipping companies (UPS has been scared away from even accepting the packages). yes, I guess they are using court orders for that. but from a "privacy" perspective - tracking what I buy and have shipped to my house, is far more intrusive then what numbers I dial.