The Electronic Privacy Information Center (EPIC) urges FTC investigate Googles Store Sales Measurement tool that tracks consumers offline shopping patterns for profiling to further improve sales through online ads. The tool was introduced in May and promises to allow you to measure in-store revenue in addition to the store visits delivered by your Search and Shopping ads It can allegedly track approximately 70 percent of US transactions to establish a clear connection between online user activity and offline purchases, yet Google refuses to reveal its data collecting methods.”]
Source: https://www.bitdefender.com/blog/hotforsecurity/ftc-investigates-googles-offline-shopping-tracker/