“They’ve built these massive laboratories where they can track what you buy with your card and sort of deduce a lot of things about you, based on those patterns. So, for instance, a good example is the study done by Canadian Tire in 2002. Canadian Tire is a big retailer that sells all types of things. It’s like Wal-Mart.
“What one of the executives there did, he looked at how people were using Canadian Tire credit cards and tracking what products they actually purchased. Then he found out that people, who for instance buy premium wild bird seed, it turns out that they very infrequently went bad on their debts. Whereas people who bought chrome accessories for their car, they walked away from their debts more frequently.”
(https://www.marketplace.org/2009/05/15/how-credit-card-companies-track-you/)
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