It's kind of according to the available food in the surrounding area. Hogs, like deer and pretty much every other mammal, will go for the food easiest to access. If they are especially hungry or the food in the feeder is especially enticing then hogs will most definitely route under that fence in no time at all. Hogs are especially good diggers since they root for many of their favorite foods so digging a little trench under that fence would be no real obstacle at all. But if memory serves me correctly in Falcon's descriptions of the surrounding areas of his hunting places, their choices of food stuffs are pretty abundant so actually working for a small meal from the feeder would not be necessary.

Some people seem to think that animals other than ourselves do not have the capacity to "reason" but those people are foolish to think that. Hogs and many other animals actually do have the capabilities of reason and are MUCH smarter than some people give them credit for. Having hunted hogs for an abundance of years, I have seen them do some things that would require serious thought processes from a human.

Top, you are correct in the fact that that fence wouldn't stop a hog in South Texas for any amount of time. But the food choices in South Texas differ greatly from where Falcon lives. While fantastic browse for deer are available, hogs have to work a little harder for food stuffs than deer around there than they do at Falcon's properties so they focus in pretty hard on deer feeders as a learned response. All this boils down to simply, hogs differ in each and every area.