I have an Enhanced Driver's License from Washington, which comes with an RFID protective sleeve to keep it in.
From the Washington Department of Licensing EDL FAQ page:
The passive RFID tag embedded in your EDL/EID doesn’t contain any personal identifying information, just a unique reference number. In addition, the tag doesn’t have a power source and cannot transmit data unless it is activated by an RFID reader. When you get an EDL/EID, we will give you a security sleeve to protect the RFID tag from being activated when you are not at a border crossing station.
What am I exposing myself to by not shielding my card properly, and therefore, is it necessary to keep my EDL in its sleeve at all times? It's rather cumbersome to do so. Or should I only keep it in its sleeve when abroad?