That small “dot” you saw was most likely where the tire manufacture marked the lightest spot of the tire, so the installer could line it up with the valve stem when mounting. Look at most tires and you will find a small dot (blue, red, white, or yellow) next to the valve stem. Sometime it will be on the undercarriage side of the tire. Don’t take my word for it, ask an installer.
Nope. This dot was not aligned with the Schrader valve in the photo. Additionally the document mentioned that the tire is not the only place marked.
This is a comment from a Gun Site instructor: "I don’t know how widespread this is becoming, but the info regarding the NSCA Nationals in San Antonio is correct, as all of us who compete in sporting clays know. Competitors there were having their vehicles marked with a small adhesive dot on the rear license plate or rear bumper, then followed for miles and having their vehicles quickly and efficiently broken in to when parked for lunch..."
The email I received had a pdf attached. I'm not very proficient with HTML, so I googled "Gun Lovers Public Service Announcement" and found a link irt to the same PSA (if you're interested, and it has a link to the photo I saw):
http://forum.bearhawkgroups.com/viewtopic.php?t=6191&sid=be171fea3c5e540b6c84883066bf9407