alt Hacker NewsAdvertising is a monetary transaction between an advertiser and a publisher. The customer (or product) is not involved in the transaction; it is their attention that is being bought and sold.
That's a different model than paying a technical writer to do technical writing.
You're contrasting authorship with distribution. The advertising equivalent to paying a technical writer is paying an ad agency to create the ad. The customer isn't a party to that transaction either.
But now how are you distributing either of them?