I love to stain it. It does make the hardwood faces match with the ply better but to me, and this is personal preference, I think the stain brings the grain out.
I'm not a snob though, I have a lot of boxes I have made from walnut, I love the natural look of walnut too.
Just depends on what it is I guess.
Figuring out how to do something you have never done is what makes a good challenge.