The Church places vastly more importance on temples than BYU sports, and they just aren't going to drop half a billion dollars on a new football stadium for BYU.

And the Provo temple was expensive to maintain and needed significant (expensive) earthquake-proofing, so it was better to just knock it down and rebuild, so you can't really use that as an argument about how the church isn't very utilitarian in its building & management of facilities.