I agree with you. It was location, and timing foremost . Georgia and Alabama were in the heart of it location wise, and timing wise. Arkansas on the other hand was at the far end of it location wise, and in the middle cause wise. I think it was easier, and cause effective for your Georgia and Alabama ancestors to side with the CSA. Those on the border may not have had an easy choice because the power of the day (front lines) for that immediate location may have waxed and waned.
Regardless of the issues, if even they were clear on that, you have to survive first and foremost. And you generally side with the side you live in. Can you imagine the difficulties in siding with a foreign nation if you live in the USA? The same in that day. Let alone do you really understand issues of both sides, or do you get the propaganda from the side you live in? Most sheeple then and now just go along with what everyone else does regardless if it is right or wrong.
2.) As you state: ["Now that's downright funny but to be expected. Nothing against the author of that letter but there were others in the Union Army who were not so picky on taking things."]
Even as the author stated they did take things but, would try to return when possible. Not that they did in all cases. Also location and time. I'm sure in some locations the punishments were more severe than in other locations. This author was speaking of just that area and at that time.