[jester]

There are a couple problems with foraging and the rules cover it pretty well.

After a while they get harder and harder to find. Add the fact that more and more people are foraging for wild edibles and game that an area would be picked clean, and in some cases to the point it would have a hard time recovering.

Another factor, foraging is seasonal. This strikes home often in that show with Les Stroud, Dual Survival and Dude You're Screwed.

Then, there is the knowledge of edible items in an area. Some things in one area (or season for that matter) can go from edible to poison. Or just look alike items. A prime example is mushrooms.