I don't understand why someone living in the city limits would think that they're private property somehow translates to being a soverign nation, that city code doesn't apply to you. And second, guns and alcohol. Yes. Great idea.
Tangentially to you point. The statute RSMo 571 defines
what intoxicated is under the law.....sort of. RSMo 571 also defines what is the (what qualifies as) unlawful use of a weapon
while intoxicated. The words substantially, negligent, and unlawful have specific legal meanings.
As I stated, a local LEA would have a very very very hard row to hoe if they attempt to gig you for popping a cool frosty friendly while on your own front porch. Considering that it is a
defense against prosecution while tanked when you lawfully defend yourself or another per RSMo 563 being intoxicated and not meeting the definition of intoxicated per RSMo571 nor handling your fire arm as described in RSMo 571, essentially means that downing a brewski is not illegal on your own property.....unless of course you is passed out on your front lawn. Which, by the way, means that you can not be charged with a unlawful use of weapon cuz you is passed out and not capable of using anything other than air.