571.030. 1. A person commits the crime of unlawful use of weapons if he or she knowingly:
(8) Carries a firearm or any other weapon readily capable of lethal use into any church or place where people have assembled for worship, or into any election precinct on any election day, or into any building owned or occupied by any agency of the federal government, state government, or political subdivision thereof;
4. Subdivisions (1), (8), and (10) of subsection 1 of this section shall not apply to any person who has a valid concealed carry endorsement issued pursuant to sections 571.101 to 571.121 or a valid permit or endorsement to carry concealed firearms issued by another state or political subdivision of another state.
I am no lawyer but this appears to me that as far as state law is concerned, citizens are allowed to carry firearms into these places if they have a valid CCE. It doesn't specify either open carry or concealed carry being prohibited if you have an endorsement.
I could easily be missing something here being a newb, so if anyone knows more, please feel free to correct me. I also am unsure as to the federal law restrictions with federal buildings and how they play into this as well as gun free school zone restrictions should these meeting places fall within one of those boundaries.
The problem in Missouri is that for open carry, you have to be aware of the local ordinances because theywill supercede state law.