Another consideration: If Pop is going to forfeit a game by not playing the Big 3, the Jazz is the perfect team to do it against. If the Spurs were to beat Utah again, they'd probably get knocked out of playoff contention. But if the Jazz win tonight, they are still in the thick of things and it will cause teams like the Mavs and Nuggets to try harder down the stretch.
And honestly, keeping the Jazz alive isn't a bad thing since they don't appear to be capable of beating the Spurs in a playoff series.