I think the answer depends on who you ask, when you ask, and why you are asking. I've been told so many reasons why, I have no clue what to believe.
I have been told that a survey was given to season ticket holders asking about their preference.
I have been told that many of the folks who work the games complained about having to stay so late, especially if they have obligations (church, for example) in the morning.
I have been told that many restaurants and bars requested the afternoon start times, because they see a big spike after the game.
I have been told that games were moved to afternoons to accommodate those fans from Idaho Falls who didn't want to drive back late. Both of them.
I have been told that attendance studies were done which indicated there was no difference between afternoon or night games.
I have been told that games were moved to afternoons so fans could catch regional games on TV at night. Seriously.
Kyle Franko had an article in the paper and on his blog this week about attendance at ISU's home openers. Relying on his numbers, I looked up to see what the start times were for the past 10 home openers. Four of the ten games started at 4:00 or later. The average attendance for those 4 games is 6,863. The average attendance for the 6 games which all started earlier in the afternoon is 5,434. Are there other factors which could be involved? Probably. I do know a lot of people who have never attended an afternoon game because it interferes with work or children. Take this Saturday, for example. There are tons of parents and kids who are involved in youth soccer games, not to mention other activities.
I would like to see some night games. You may lose some people who can't go at night, but you're going to pick up some who can't attend during the day. Right now, ISU is playing to the 60+ demographic. Lots of long term stability in that. Not.