Limits of patriotism

I came to the USA expecting high levels of patriotism, emotions usually not publicly expressed in Czech Republic. Yet, I was not really expecting to see that "USA" written on the road that is about to be repaired.

To explain: before the road is being fixed (or dig into), signs appear to mark the beginning, end, where some utilities (gas, water etc.) go and so on. Almost every single sign ends with "USA". I'm not sure what this is supposed to mean. Probably it has some meaning I'm not aware of. Or people are just crazy.