whatever they want. If someone doesn't like it, then they can choose to spend their money elsewhere (or lobby for why they believe the funds would be better invested elsewhere).

How they allocate the funds is not a moral/ethical issue. They could use the my tuition to pay a professor whose class I'll never take, build a building I'll never walk in, support a research project that has no effect on me, or pay for a sport I'll never watch.

What you're saying makes no sense whatsoever. You're the customer who can decide if your tuition is worth paying or not. What BYU does with the money is up to them. IMO, athletics are a good investment and I have no problem with them allocating tuition money that direction. Turning this into an ethical issue is bizarre.