Godaddy does keystroke logging (it's their web page, why not).

Without your actually clicking "buy" Godaddy knows your domain.

Try it! Using a throwaway email, fill in the Godaddy form with a novel domain name, email contact, etc, but don't click on any "next" or "buy" or even "search" buttons.

Sit back and wait. The spam will start to arrive. The spam will be web and SEO and logo and app developers.

They are "affiliates" and they pay Godaddy for details of new DNS domains. They don't pay much perhaps, but they are getting first-hand info of your DNS ideas.

That's where the front-runners get the info; domain-squatting is free so it's free money to them.