The first few weeks of a kittens socialization are very important. That is when they learn that it's okay to bond with their human cargivers. What you're describing is basically a feral sort of situation, or maybe more accurately a stray situation. I very much doubt that someone who is allowing their cats to reproduce unchecked is going to go outside to properly socialize the kittens. Whatever the case, the chances are that those kittens are learning to depend on other cats rather than on humans. Those kittens can eventually be turned around, but generally will remain less social throughout their lives. By going to your shelter you be supporting the proper system for homeless animals. Also, it makes more sense medically. Sure there is an adoption fee, but in most cases for that you are getting a cat that has its shots, and has been fixed. My cat even came with a microchip. I think you should go to the shelter. It's kitten season so the shelters need ever adoption that they can get.
