The life of the 3-Ring binder spans several decades and with it the catalogs that live inside them. Imagine your company has a few dozen (or more) vendors and you need to keep a reference of their products at your finger tips. This is where the loop stitch catalog really shines in the binder. The loop (by design) keeps your catalog place marked in a binder by standing it out from the others. Hole drilled or hole punched pages won't stick out as much and therefore your loop stitch catalog is the first one that gets opened.
Bonus: Loop stitching prevents the destruction of content and type that hole drilling causes.