All companies make money by adding value, the goal is to maximize value created while minimizing the cost and then benefit by charging people based on that gap. The niche is really the type of value your creating and you need to pick a niche is the correct size for your needs and capital. There is a world of difference between the ideal niche for a collage student trying to make some beer money, an unemployed coder trying to make rent, and 3 collage friends who just got 2 million in funding. The smaller the company the more nuanced it's approach and the smaller the niche, can be. What might look like a product feature to Microsoft may support 5 different tiny software companies all going after different angles.

The specifics relate to the market and the kinds of product sold. You are not going to make money shipping individual 50lb bags of dog food to people, but you might be able to make money shipping pallets of dog food to people. Things like building communities or creating content are really just another form of advertizing that is theoretically cheaper to create in the long run than Adwords.