Where are they getting "petabytes" of daily data from? Even if you took every single transaction anywhere near the industry, in all its details, and represented it in a verbose format like JSON or XML, that's still only kilobytes of data times billions of transactions = terabytes.

If they were gathering tons of video, maybe. Or vast numbers of high-precision sensors generating data continuously. But I didn't see anything like that.

It's just hard for any human activity to generate that much data. Is "petabytes" just some kind of hype, or is there something I'm missing?