A one year rental in the hand with a scholarship that you recycle next year is more than worth the trade off against the off chance that your dream player comes available midseason. Sure, a lot of teams choose to only go with 7 or 8 because that's where their big talent drop off hits (unless you're Tom Izzo, Leonard Hamilton, Kelvin Sampson, or Mark Few and you have a dozen guys who can play and you use that to your advantage) but there's a real big difference between preferring to play 7 or 8 and only having 6 to 7 healthy players available.
That was painfully clear this year with us where we had one empty scholarship, one player on a sit out year, and two raw freshmen who needed a redshirt year and battled injuries. We were a fringe bubble team at one point this season at 15-9 (6-7) with wins over FSU and Rutgers but in that game against Georgia Tech to take us to 15-9 we really only had 6 players available plus Coulibaly. We did not win another game until the ACC tournament and, while there were also locker room factors at play, hitting the physical wall while trying to compete with the likes FSU (who played 11 players at least 12 minutes against us in February) was a major reason why.