Mysterious missing tire pressure valve caps

We park our car on the street in a big city. About a month after we bought the car we noticed that the two street-side tire pressure valve caps were missing. We then bought off the internet some “thief-proof” valve caps that require a key to take off. Things were going great until this week when once again one of the caps is missing. Other than general annoyance, what’s the point of stealing these things? And what can we do to keep from having to go through so many tire pressure valve caps? What are the consequences of driving around without them?

I could not even start to explain why someone would go to the trouble of stealing something like this unless it’s one of the local 15 year old punks just causing trouble.

The downside to not having a cap in place is that it allows dirt to collect on the Schrader valve through which air is added. The next time an air hose is connected this may push dirt into the valve seat and the tire will lose air pressure due to the leak caused by the dirt.

The cap is there to prevent dirt and debris from getting to the valve. The cap doesn’t do anything to maintain tire pressure.

I’d suggest just buying some cheap plastic valve caps at an auto parts store and replace the ones that go missing.

I can’t imagine why anyone would take the trouble to steal them, but I guess someone likes valve caps.