There's an oft-quoted saying that academic politics are so vicious because the stakes are so low. (I've most often heard it attributed to Kissinger, but this response on Ask Metafilter provides a much better history of the aphorism.)
This morning in the shower, as I was pondering my election to RIT's senate for a third three-year term (not consecutive, thank goodness...I had a several-year respite), I came up with a very different assessment of why the politics on university campuses can be so bitter and personal. It's not, I think that the stakes are so small. It's more that the faculty at a university are, more often than not, in it for life. Tenure gives us job security, yes, but it also turns the university into a very large and often dysfunctional family.
We worry about the small details of day to day life in the university because most of us know this is where we'll be until the end of our professional lives. We've seen how supposedly minute changes in policies can result in long-term and significant impact to our day-to-day lives. Do we overreact to many of these small issues? Absolutely. The same way that many of us overreact to things that our family members do.
The reason I'm willing to go back to the senate for another three years of (often hellish) bi-weekly meetings is that this is my home, and much as I may not enjoy the maintenance of these academic family ties, I know that I'm worse off if we as a faculty neglect them.
So, no, I don't think I'm crazy for going back for more. And I continue to believe that shared governance is only as useful as the energy that all the participants are willing to put into it.
Getting involved and making a difference sure beats complaining that no one else is doing it . . . ;-) It's great that you are willing to engage in this type of university service given that you are at a point where you do not have to do so. RIT is lucky to have you!