Well, to be fair about it, CCW has been illegal in MO for ~125 years, so it's not like this is all about some modern-day gun-grabbing legislation.
If it's like most of the anti-CCW bills passed in the south after the civil war, the purpose of the racist edict was to prevent 'them there blacks' from defending themselves and their families from thugs.
That was the case in most of the states which have within the last few years set up CHL systems. Texas law goes back to the 1870s sometime. Like other such laws in other states, it was designed to assure that newly freed Blacks, and in Texas "Mexicans" as well, would be unarmed. The Sherrifs did not enforce the law against the likes of the KKK, or for that matter against citizens of European ancestory in general, save the odd mick or daygo of course.