For those who don’t remember them:
In 2000, they had the bright idea that people would leave these connected to their computers so that advertisers in magazines could put a barcode on the page to go straight to a webpage with info about a product or a product catalog from someone like RadioShack would let you scan it to take you straight to an ordering page. Similar to how QR codes function often today.
The problem was that in 2000 almost nobody had an always on internet connection unless you were lucky, wealthy, or in school. And URLs are really easy to type.
They stopped giving them away in 2001.