In computer programming, sorting is important when you want to sort something, and it's occasionally important to use the correct sort. Normally sorts are provided by a framework or library that are going to be good enough for most purposes (although if you're the one writing the framework/library, that's another story).

I suspect that that's not your real question, though, and that your real question is "I'm studying algorithms and they sure seem overly interested in sorting. Why is that?"

It's the same reason people seem too interested in factorial when you start talking about recursion: it's a thing you already know how to do, but now you're going to look at it a new way. They're showing how different types of algorithms can make a big difference in performance. They're showing how to calculate the growth rate of time required as the number of items grows large.