Mako,
Perhaps your request is too difficult to research. For example, where would I go if I wanted to find out if Central Michigan has had an off-field arrest in the previous two seasons? Your request borders on the impossible, so I wouldn't assume a non-answer to your request proves anything. Secondly, why are you worried about other programs? Let's focus on Marshall. I don't think it's relevant if other programs have off-the-field problems or don't have off-the field problems.
I will agree with you that many programs do have off-the-field problems. However, when a program has both off-the-field problems and on-the-field problems (underachievement, no bowl games, no championships, lethargic performances in bowl games, out of shape players, etc), it makes fans begin to wonder.