In 2011, it is fair to say that everyone needs a computer of some sort. Most of us though, don't need one particular model over another. Sure, some work in media or some other specific field and truly require one OS over another, but that's not the case for the average user.
That said, unless we're buying the cheapest thing out there--simply to meet a basic need--the vast majority of us are buying based on want.
In my opinion, any variation of Mac provides a superior experience. With the exception of gaming, there is nothing that a Windows PC does unquestionably better, that's all based on opinion.
In short, we all bought because we needed a computer, and maybe needed a portable one. But we chose the model we chose because it was our preference as consumers.