They have to do that. They do not want games where 40,000 Ohio State or Michigan fans show up at their stadium (yes an exaggeration). Also, they have a smaller alumni and student base than a lot of other B1G schools. A smaller environment makes perfect sense there.
I just shake my head a little when we worry about making our stadium too big. Back in the 1980s, there was no issue getting over 70,000 to attend a game (and well over 75,000 on a consistent basis). If the team starts to win consistently, I expect the crowds to largely come back (we have been so mediocre as a program that fans are largely staying away). We did average nearly 62,000 (close to capacity) a game in 2008, until the program began to crumble around Zook. If the stadium was to renovate a bigger horseshoe section, and got capacity to around 70,000, it would be a similar capacity to what the stadium had before the Illinois Renaissance Program was completed in 2008. I remember a lot of grumbling about reducing the capacity to 62,000 back when I was student at the time. Now we are possibly grumbling about getting capacity closer to what it was before?
I am in the camp of no major structural changes needed right now, but if revenue started to really flow in (meaning the team is getting good consistently) requiring some updates (and more capacity), I could see the need to add seats back in the horseshoe, all while keeping the rest of the stadium as is. No need to change the East Main at all. It is architecturally beautiful and historic, and I would hate to see it get modified to look similar to the West Main.
It's also worth noting that the 2007 season likely could have drawn way more fans per game. However, due to renovations, capacity was only about 58k that year:
There is no reason our attendance would not grow significantly with consistent success. After all, we have gone from 35k fans per game to over 50k fans per game in barely two seasons. Just compare us to Iowa ... a program that has had enough success to convince fans to make attending a game a habit. Before anyone gives me the "no pro sports in Iowa!" excuse, their basketball attendance is even worse than our football attendance on a comparative basis. Fans show up for a winning program in 99.99% of cases.
1. Illinois has over 35,000 undergraduate students and over 56,000 total students. Compare that to only 22,000 undergraduates and 31,000 total students at Iowa, who draws 69,000+ every game.
2. The Champaign MSA has over 235,000 people. Compare that to just 180,000 in Iowa City. If we expand it to MSAs within a reasonable drive, it might look something like this:
897,000 for Iowa (Iowa City, Cedar Rapids, Davenport, Waterloo/Cedar Falls, Dubuque)
1.25 million for Illinois (Champaign, Bloomington, Peoria, Springfield, Danville, Decatur)
3. Iowa has about 300,000 living alumni, and WAY more of them live out of state than Illinois alumni based on the stats I have seen. Meanwhile, UIUC itself has over 500,000, with the U of I System having nearly 850,000.
Even if we take it on faith that Iowa has this insurmountable edge when it comes to support from non-alum fans instate (which I would certainly dispute at least for Central Illinois vs. Eastern Iowa; Chicagoland is another story), simple math just says there are at LEAST as many "potential Illini fans" as Iowa fans. If we start winning 7+ games per year, we can absolutely get significantly more than 60,000 fans at our home games.