Tiger Stadium sells out for each game and has been in the top-10 in attendence for decades. There are no shows, just like any school has, but its not related to ticket prices--the tickets have been bought.
1. Television--almost every game is televised now, even the OOC games on pay-per view. When the weather is bad for a game against a Div-AA opponent and your arthritic knees are acting up, some folks just stay at home and watch it on the HDTV.
2. Upper Deck Syndrome. If your seats are in the corners of the upper deck, sometimes you just don't go or you upgrade from a scalper. It's a long way from the field and the view is lousy. Schools with high upper decks in the endzones have a lot of trouble with no-shows because the view of the field is so bad. There is high turnover for these seats.
LSU doesn't have a problem unless people stop buying tickets. That didn't even happen in the 1990's when LSU had 8 losing seasons.