A discount at checkout can cost less than a dollar and still give a company something useful: your phone number. Suddenly, the store can connect a purchase to a customer profile, send promotions, and potentially match that information with other records. Your ten-digit number does more than help people reach you. It can help businesses recognize you across different interactions.
The surprising part is that companies do not necessarily need to know everything about you. They just need enough information to connect the dots. A phone number can help link an email address, a shopping account, a delivery record, or a marketing database to the same person. That makes this ordinary piece of contact information useful for far more than phone calls.
