Well, that's a horrible generalization. I go camping up in Wisconsin all the time and I'm very respectful of people's peace and quiet and try to keep my voice down and we don't get rowdy, especially at night when people are trying to sleep. But sure enough...every single camping weekend there's always at least one campsite...one campsite that doesn't understand that other people are surrounding them and sound travels very far at campsites. They sit up all night, play music and drink beer and get rowdy and crack pieces of wood and keep throwing them into the fire. The ranger comes by, tells them to turn it down, and they do for about five minutes and then they get REALLY drunk and usually somebody picks a fight with another one and then the ranger comes back with a police officer and they get tossed out on their asses, but only after it takes them 45 minutes to throw their crap in their truck. And their license plates are ALWAYS from Wisconsin. Always.
But do I say that "that's your typical Wisconsinite?" No.
I've seen this in other places, too. When we go to the out island of the Bahamas, we've bumped into other Americans who bemoan the lack of niceties- but want to be there to "get away from it all". It's not really about the locality people come from, but instead the attitude.
And because the nearest major city happens to be in Illinois in our area, many of the people who fall into this category are from Illinois. There are jerks from every state, of course- but the people who come into a community and try to help us "better" ourselves are the ones who tend to get the most derision. Unfortunately, many tourists claim to want to be in the wilderness, but they get really pissed when their iphones don't have full coverage in the wilderness. Those people are not generally those who are local, or those who have great appreciate for unspoiled and wild areas.
There are perfectly lovely city folk, but there are also those who think that being out of suburbia means they have the right to tell others how the world works. Those are "FIBs".
If that seems to be an unfair generalization, maybe it is. I wonder if one of my neighbors, in his overalls and unshaven face, who looks like a drunk Oak Ridge Boy, would fare well in their company. Oh, he has a master's degree and all- but often the ones we refer to as "FIBs" don't appreciate that. That is why they are FIBs, after all.
(And maybe the ill behaved campers with WI plates are from Milwaukee, where they are just northern FIBs.) Kidding, kidding- sort of.
I just got back from a get together at a neighbor's house. Most of the people in the room have a master's degree, but some only have a BS. I am the dummy in the group, with no degree. I have been in about 30 countries worldwide, though. We are not a group of uneducated bumpkins, but "FIBs", no matter where they come from will treat us as if.
That is the point of the nickname- not the particular locale, but instead the superiority complex assumed by some. It's not necessarily Illinois or Indiana, but because we are in the midwest that is often the case. We don't get too many tourists from Lincoln, NE or Des Moines, IA.