Using other people’s library card to get ebooks

I followed an online discussion about accessing ebooks using library cards that you obtain online. (The discussion is behind a password so I cannot link you to it. ) People said there were libraries that would send you a card regardless of where you live. They then use the card to checkout ebooks from their location. It sounded like people were accessing ebooks from libraries in other states One person had a slightly different approach: “Also, if you know someone in another city/state who has (or is willing to get) a library card, ask them if you can use their number. I often use my SIL’s library account from another state, because they have a great selection of eBooks.”

Anyone heard of this happening?