I'm not sure if that's true, the vegetables and meat do cost something. If you do plan on making stock regularly, I've recently found that a pressure cooker is a great investment. The result actually tastes better after far less time.

But I would say if you're just cooking something quick and cheap for yourself, there's nothing wrong with bouillon cubes. In a sauce it's better than just salt which is probably going to be the alternative.

It's true. I spend less on vegetables to make a gallon of stock than I do to buy one quart at a grocery store, and mine is better. Even when I'm doing a beef stock and have to buy the bones it's still a little cheaper, though in that case not much. But the difference in quality between homemade beef stock and store bought is far larger than the same difference in chicken stock.