Actually, I kinda answered my own question. Any input or contradicting info would be appreciated, as the answer is one that I don't like.
Missouri does allow open carry of firearms for those age 21 or older. However, city, county, and municipalities are allowed to pass local laws and ordinances restricting this. It is advisable to check local laws and ordinances before openly carrying a firearm within Missouri.
Amaz-uh-zing what one can do if he looks before he leaps, eh?