Eh, I'll just say it explicitly so people get the point.
In 1994 ESPN bought Ohlmeyer Communications Company, owned by famous media executive Don Ohlmeyer. Prior to that purchase OCC had bought Creative Sports, another media production house. OCC was based in LA. Creative Sports was based in... Charlotte.
ESPN rebranded OCC as ESPN Regional Television and consolidated all operations in... Charlotte.
They did so in... 1996.
All of ESPN's regional production has come from the Charlotte facility ever since. The old "Big East Network" syndicated football and basketball packages? HQ'd from Charlotte.
Needless to say, when ESPN launched the SEC Network it made financial sense to operate the channel out of... Charlotte. Because it would have been expensive, duplicative, and generally stupid to open a brand new production facility in, say, Oxford, Mississippi.
When the ACCN was created it made sense to also operate it from... Charlotte. For the aforementioned reasons.
If ESPN someday launches the Big Sky Network you can be pretty sure it'll operate from... Charlotte.
So yeah, there you go.