Have you ever seen those custom road signs people plant on the side of the road for Yard Sales, Home for Sale, Insurance Quotes, T-shirts, or a local dating service? Well these are usually made out of a form of PVC Foam. It is extremely weather resistant and can be printed with bright colors that won’t fade over time in the sun.
The are also extremely cheap to mass produce so that is one reason you see them everywhere, and if they get taken down, you can just plant a new one. With the election coming up next year, I’m sure you’ll be seeing a lot more pvc foam boards in the near future.