I'm not sure why I only noticed this 8 pages in... but I feel your pain!
This Fall I had the valve stem covers stolen off my Works while I was buying groceries. They actually tried to steal the entire valve stem (since they are blue I assume) and in the process of what appears to be an attempt to rip them off the car they ended up leaving me with 2 flat tires that couldn't hold any air. I had to pay to get towed to a shop, retighten the insides/stems to refill, and I'm still missing the f**king covers. Unfortunately you can't buy just the covers from Work, and a set of the valve stems with covers is like $80... so it looks very sad with my pretty blue valve stems and stupid black plastic covers. I would TOTALLY steal them back if I found them on another car! Even if I had replaced mine. And I would have a hell of a time resisting the urge to kick in their window too just for the money and frustration it caused me...