A couple of reasons actually: They are a team in a crappy state. I did not want to build a team in pipeline state like CA, TX, or FL, as you have an advantage with some VERY good recruits regularly coming from those states. They have sucked for a really long time. Nobody ever picks this team when running a dynasty. There is 0 program tradition, so can't really be compared with any other coach in team history. Plus, there stadium is so shitty I actually kinda like it. Basically an airplane hangar with some turf inside it.
I like to use Idaho in offliners as well. I have one going on with Idaho atm. My brother and his wife both work for the university so I kinda have a soft spot for 'em.