This feels a bit like the B1G presidents prematurely postponing football, only to realize coaches and players (the ones who stand to lose anything) were completely against the idea.
For the Citadel, they willingly agreed to play in this game because:
1) it helps fund (maybe even fully funds) their athletic department, including scholarships for the football players
2) it gives players at a smaller school much broader exposure than they would otherwise have
3) it offers those players the chance to prove themselves against elite competition
4) it gives those players bragging rights that likely none us can claim - they played in Death Valley (in other words, memories that they will carry with them)
But yeah, you think it's immoral so they probably shouldn't play. No need to consider the actual participants of the game.