As two quick examples check out the open carry laws in Texas and Arizona where registered personally owned firearms per capita is among the highest in the country.
Yes, open carry laws exist. Yes, people in the South own firearms. Nevertheless your statement that "almost everyone in southern states visibly carry guns" remains false.
A more correct restatement of your claim might be that "many" Southerners openly carry, but that's still a minority of a minority given that, per capita, most Southerners don't even own a gun. "Almost everyone" is reaching into some kind of weird libertarian wild-west fantasy stereotype.
* https://en.m.wikipedia.org/wiki/Gun_laws_in_Arizona
As two quick examples check out the open carry laws in Texas and Arizona where registered personally owned firearms per capita is among the highest in the country.