Regardless of whether or not someone is actually going to college (and a lot of people simply shouldn't be going), quite a few states in the area mandate the ACT and / or SAT exams by all high school juniors. Alabama recently mandated the ACT for all juniors, as does Mississippi.
When you factor in places such as Hueytown, Alabama, where the average scores are going to be well below the mean, it's not surprising that the state's scores are going to be lower. Very few of those kids are college-bound, and even if they are, those schools will simply overlook what are some truly terrible scores.
If you compare apples to apples, I could easily say the same about many of the schools in the Baltimore, Maryland's public school system, where often times, not even one student in a class has met the minimum standard for math proficiency, despite that state and city having spent more per capita on education than most places.
I would easily bet dollars to dimes that if those students were required to take the SAT or ACT, that they would do very badly as well, and that their scores would drag down those average scores quite a bit.