Dog Food or People Food?

Hi,

I'm really confused about 2 things. A friend of mine doesn't feed her dogs dog food because she read something, somewhere, about all the so called questionable ingredients that go into the processing of dog food. Therefore, she feeds her dogs(they're a couple of years old)a diet of brown rice, grilled chicken, fish etc. They look great and from what the vet says, are in perfect health. But I thought that one of the reasons we feed our dogs their own food(i.e. dog food) was so that they get all the nutrients they need, and to discourage begging for our food. Which leads me to my second question. I read the post here this morning about sharing McDonald's. I always heard that it was never a good idea to feed a dog any people food(even a taste)because it encourages begging, not to mention wreaks havoc and a dog's stomach. I know this from experience, because my Petey gets a little taste of vanilla ice cream every now and then, and now he's obsessed with anything I eat. Breakfast, lunch, dinner, you name it. He sits and watches me like a hawk, like he's waiting for me to drop a crumb so that he can snarf. You'd think I starve him!! I can kind of control it when it's just us, but it's embarrassing when he does it around others. My mom(who is my dog walker)had to take her lunch home to eat the other day, because Petey was "circling" and trying to get up on the table. She was afraid to turn her head for a second, because he is pretty quick when he wants something!

I'd appreciate your thoughts as I only want to do what's best for my little guy!

Thanks!