[nonameiguess]

Ultimately, all attempts at attribution are heuristic in nature. Marketers know a single IP doesn't represent a single person, but if it's the best they can do, it's the best they can do. Even for services with accounts, tracking can't be perfect. When my wife's phone or laptop is closer than mine and she's logged into Amazon Prime or Uber Eats, I'm ordering through her account. Now she's gonna see ads for gym equipment she has no interest in. Oh well. It doesn't matter how good your location, device, browser fingerprinting is when people share locations, devices, and browsers. The only way to know it's really me is to get my actual fingerprint or some other truly unique biometric identifier.