Sugar Bowl loses some of its autonomy when the SEC championship is in the playoffs semifinals or the Sugar Bowl is hosting a semifinal, it is all about creating an event from the list and ranking of teams by the CFP selection committee.
Within the CFP strata, all of the schools at that level travel well, bring huge official parties, have significant and casual followers not connected to the schools and have a significant national collegiate athletic presence, that is why they have been so slow to allow schools in to the actual playoff from the non power 5 conferences, i.e. Cincinnati, UCF, Boise State, Houston, Western Michigan, Memphis, Appy State, Coastal Carolina, etc. with solid records in less competitive conferences.
At the Alabama game this year, Neyland was chocked full of interested football fans and undergrads from all over the country, totally unaffiliated with either school, but wanted to experience big time college football on the national scale and the CFP bowls look to do that with each of their games. Expansion wouldn't be expectations to change that approach much and the likelihood of the CFP organization scooping up other bowls is not likely, they will use existing CFP Bowl venues or other suitable venues for quarter final games before pushing the competition into their existing CFP framework, further separating this process from the bowls on the periphery such as the bowls in Tampa, Jacksonville, Houston, Charlotte and Detroit, which sit in modern NFL stadiums but don't have the history or the draw the CFP crowd has.
The CFP fixed most of the flaws from the old BCS, but there are still a few human concerns in the CFP framework that expansion could fix. As long as the NCAA is out of the mix, we should all be very thankful.