Im not so sure about that. Old Big12 with Nebraska, sure, especially after breaking their long home winning streak 2x, going 9-1 against them and beating them in St Louis, 1 second game etc...then of course the two Texas schools Baylor, Tech , we were their Super Bowl. When we announced leaving, the vitriol from the league office, the officiatiing. KSU always played up for us.
In the SEC, I feel they are way more deferential. There is a certain level of respect from my interactions working in several SEC states on a weekly basis and interacting with them. We came into a league with a pre-set enemies (Bama vs Tenn, Auburn and LSU...UGA - FL, Egg Bowl etc..) that IMO we are not viewed with as much annumus like it was in the B12. They are glad we are here b/c it elevates the conference to whole new level. Gun to head, I bet the average SEC fan would have preferred to keep the SEC as it was, but they are not "mad" at us coming in like it was when the Big8 and SWC formed. We didnt break up rivalries in the SEC in the same way. In some ways, the SEC teams are glad they aren't playing some of the teams on a regular basis, its tough enough already is the sentiment i get.