Hey Jenn, My concern with eating whenever food was available is that food is much more readily available now to us. How do we gage when it's ok and when it's not if it's always a fingertip away? through the ages eating has always been something that has been done as a group and never individually. The members of a community that were sent to get food didn't find it and eat it they would have gathered enough for everyone then brought it back and then eaten it as a group. I do fully believe that hunters would have waited for a meal time.
Don't forget that a couple "berries" here or there is why most of us are on this blog