Oh now, Texas A & M is more alien to the South than Missouri is.
I'm not so sure there's any reason to feel as if the Southeastern Conference is Missouri's "second choice."
It was a long time ago that Missouri contemplated going to the Big 10, and at that time, probably the Southeastern Conference hadn't thought about expanding.
So it's not like Missouri thought about the Southeastern Conference and then decided no, we'd rather be in the Big 10; the option probably didn't exist at the time.
For this whole mess, remember, blame Texas.