Theft of original license plates - is this an issue?

[SteveR.]

I have 1930 TX plates on my Tudor. It is my weekend car, so it is often at the grocery store, hardware store, or wherever else I need to go. I only have the rear plate installed as I've wondered if someone would steal these. Since they would be reported stolen maybe they aren't terribly attractive to thieves. Is theft of original plates an issue I should be concerned with?