Comment by hamburgerwah

One other thing people may not realize. If you use your credit card at a merchant online or in person and you associate any information such as a telephone number or email with that card. Any time you use that card, online or off, to make a purchase with that merchant those transactions can be tied together regardless of whether you provide your email/phone on future transactions. Large vendors such as walmart etc now associate that phone/email and card(s) with your facial recognition information. The second you walk into the store based on your face they can pull up your entire purchase history and contact. They are now crunching that data to improve retail layouts, marketing pitches, etc and there is growing market of selling aggregates of that data across merchants.