Mr. Blue,
Shooting squirrels is not just fun. I do not know what kind of squirrels you are used to, but in CA we have far too many ground squirrels. These squirrels dig burrows that they live in (much like prairie dogs) underneath trees, or anything that they can find to make themselves as much of a nuisance to you as possible. My family has had an almond orchard for a few generations, we have fought a constant battle against squirrels, because;
1. Squirrels eat all of the almonds that they can find, leaving you none to harvest.
2. Squirrels dig under the trees, weakening the trees hold to the earth, making the trees fall over during windy storms, when we try to harvest them, etc...
3. They carry rabies, the plague, and all sorts of other diseases.
I also would not eat ground squirrel; however I understand that gray squirrels are quite good if you prepare it properly. I have never eaten it personally, but there is a person that attends the same church that I do who used to live in Arkansas and he used to eat gray squirrels often.
I love my .22 LR Marlin bolt gun; very accurate and (as has already been stated) you could probably kill whitetail with it if the need arose.