You are not always "carrying" your shotgun.....at the boat launch, for instance. Your shotgun must be encased while traveling by boat to and from your hunting site.
In addition, there have been problems with people growing marijuana and starting meth labs in the woods on state owned property.....If I accidently bump into something like this, I would like a little more firepower than a 3 shot repeater and #3 steel.
Also, for those of you who have forgotten, several deer hunters were killed last year by Chai Vang in Wisconsin....He was tresspassing and poaching on private land, and claimed he was "threatened" by the landowner (so how does that explain the shooing of an unarmed woman in the back?). I have had run-ins with bow hunters on state land who think that by putting out a pile of carrots, that gives them exclusive claim to the entire section they are in. I have had people climb out of thier tree stands and run up to me and threaten to shoot me and my dog because we were too close to thier bait pile. We have also had dogs shot for "tresspassing"....
Finally, I hunt an area near the U.S./Canadian border. There has been quite a bit of 'unofficial' information being passed around by the locals concerning the finding of illegal(mostly asian) immigrants in the marsh, brought across the border by smugglers. Ordinarily I would pooh-pooh such info as drivel and flights of fantasy, but lately the U.S. Border patrol and immigration service has been settiing up roadside checkpoints and I am seeing more border patrol vehicles than I ever have in all my years of hunting there. Coincidence? Probably, but I'd just assume have the means at my disposal to deal with 2 or more desperate and determined individuals (i.e. potential terrorists) who I might stumble upon in a marsh or parking area....I do not intend to become a victim so the can gain access to this country, for ANY purpose!