First of all, ISU is not "spending" any monies out of their annual budget to build this sort of project. Those funds are coming from generous gifts/donations by loyal Cyclone fans looking for tax breaks and/or looking to put their name on something for posterity. Additionally, annual revenue streams would certainly be in excess of a "couple of $Million".
Secondly, many programs that have not "capped out" ticket sales are doing these sort of projects. Frankly, these sort of projects bring new dollars to the revenue stream...they do not just redirect existing dollars. There are a lot of business that want to use these venues for entertainment and individuals with the resources that would prefer to be sitting in a heated box for that game in November as opposed to freezing their keister off in the elements. By the way, ISU has been playing FB for almost 120 years and you think the program is not "mature"?
Lastly, your comment about increasing "hot dog sales" shows you to either be naive or ignorant. Have you ever been involved with a luxury box? You pay an annual fee to use the box...these fees typically range from $15,000 to $100,000 per year. You have to buy your food...which is typically something a little more upscale than hot dogs. And you still have to buy your tickets.
I guess maybe some of you need to get outside of central Iowa / Ames and see what the rest of the world is doing...there is an "athletic arms race" going on and our failure to keep up today will result in it being increasingly difficult to catch up going forward. Or maybe you were OK with ISU being shunted to a lower tier conference during all of the conference realignment talk?