He's a legacy donor that likely has been sitting in his seats for some years, surrounded by like legacy donors. It's not to spite her because she's a Utah fan but out of respect for being a legacy donor and him paying a ton of money, and those around him doing the same, just to sit with opposing fans. There's something to be said for the legacy donors to want to be surrounded by their school's fans.
Sure things can be a little more hyped or sensitive with this rivalry, but I think you're reading the OP's point wrong if you think it's strictly to punish a Ute fan.