When you swipe your credit card purchcase information is captured. This information is for you, your credit card, and the processing system that runs the company’s point of sale system. The information for you is to track your cash in and out. The information for your credit card company is to help them assist you with tracking it, tracking spening behavior to avoid fraud, but now they are store your data. It cost them money to store your data so they let someone else store it, or they sell it entirely. This is where the third party come in as the processing system or as the data storage facility.