how's it legal to sell something that spams a site? and for that matter, how are account creators legal? where is the law when it comes to using "Craig's List" or "Kijiji" or "G-mail" or "Yahoo" in advertising your product? Aren't you profiting off their copyright name?
In some countries it's not legal. No that's fair-use. The mentioning of a product isn't a copyright or TM infringement. When Pepsi ran commercials saying it tasted better than Coca-Cola it was legal.