The happier your fans are, the more of each type of ticket they will buy, and fans will buy the most expensive tickets they can afford.
That is straight from the game manual.
So basically, if your luxury box prices are 900 dollars, then any fans with a budget over 900 dollars will buy a luxury box, anyone with a budget of 899 dollars will buy a courtside seat. So as you can see, the number of luxury boxes sold has nothing to do with the number of courtside seats you have. It's all about the price and what your fans can afford.
Consequently, bleachers are very important, because if your fans have a high budget they will buy one of the other seats, but there will be a lot of fans that don't have a high budget and will not buy the other seats under any circumstance, and this is where bleachers are good because they cost less and so fans that can't afford a lower tier seat will buy a bleacher seat (provided the bleacher seat isn't too expensive).
Do you understand?
Basically, bleacher attendance won't affect the attendance for the rest of your arena.
So you should build up your bleachers and other seats now because you are missing out on a lot of income each week.
Hope that makes sense.