If you want documentation, just read their agreement when you explore the card deal.
These guys, along with many other entitles, state in their fine print that you give them the right to track your web site visits, access your contacts, and sell your private information to their āpartnersā, whomever they may be.
Just the other day, someone posted here about a new navigation app for truckers and rv owners. It sounded pretty good, so I downloaded the app. In the install process, I carefully read their agreement. It stated exactly what I said above - they were going to harvest and sell my private info. I declined their agreement and did not install the app.