It is common practice to tag your checked bag or even hand carried bag with a tag. How are you going to fill the info there?
In old days, mobile communication device is rare. If you cannot find the bag at baggage claim area, you rely on transportation service provider to contact you and deliver the bag per the stated address even though you report them about lost bag. Therefore, you have to provide the accurate address and contact information.
Now, the scenario is reversed. If you cannot find your checked bag, you contact the transportation service provider to locate the lost bag with ticket number assigned at check in and tell them where to send to and how to reach you. Therefore, the bag tag shall only serve an identification means and avoid putting too much privacy information (address, contact number, email) there.
In addition, the tag attached to the checked bag has RFiD to track its routing through out the entire journey and you can have App from carrier to track your checked bag status too. All these make the life easier.