I have heard about this before on auto-x events and have heard of people losing their warranties on new cars but it looks like the insurance companies are starting to watch drag strips too !
Here is a link to a guys story:
http://www.racersden.net/forum/showt...7&page=1&pp=20
Bottom line, take off or cover your tag at any tyoe of track you go to.
Just a little FYI for you guys / gals so be careful.