US Immigration from Netherlands

I received my 10 year Green Card last week (yay!), and it came with the little paper envelope that always come with cards from USCIS. But this time was the first time I actually paid attention to what was written on the little envelope. It says: "We recommend use of this envelope to protect your new card and to prevent wireless communication with it."

I'm intrigued. How does this work? Who or what would want to wirelessly communicate with my Green Card? And how? And why? What information would my card wirelessly communicate to whoever is communicating with it? Also, how exactly does a little paper envelope prevent all this? I am genuinely curious. Any thoughts/ideas?