They played there two years ago, they also played there to start the season (in a game that actually mattered, and had pretty decent attendance - not as many fans as South Carolina, but still decent). It really made little sense for the ACC to send them there for the 3rd time in 2 calendar years, but FSU's omission from the CFP threw everything for a loop.
15-20 years ago, this location easily sold out UVA/West Virginia, UNC/West Virginia, and UNC/BC matchups, and last night they barely had a need to open the upper level. Bowl games are slowly dying on the vine (attendance wise), but ESPN needs the programming and the bowl execs sure don't want to lose their golden goose, but they've got to find a way to incentivize the players currently opting out to play in the future.