I open carry quite a bit. If it's some government buildings, including those run by the state or county, I'm pretty sure they have the right to say "Not in here." They don't, however, have the right to say, "Not in McDonald's!". McD's can put up a sign, but it carries no legal weight here in CO.

Honestly, someone seeing a gun in a holster of someone laughing and having a good time with friends or getting food at Tokyo Joe's and getting freaked out is a personal problem.