I often find including a file much more easier to work with and less messy. When you have to reiterate an output so many times, it just makes it messy for you when you have to redo the output strings. It is also good practice to separate logics, this way, you can manage things in a much easier way.
That’s just how I see it. Not really an advantage.
The advantage of a function is that it needs to explicitly state its dependencies, whereas an include automatically uses the available variables (so you have a hell of a time figuring out where that variable that the include uses comes from or even what it’s supposed to contain).