Why not use munich/honey malt in steeping grains

So I'm dying to try this after reading all the rave reviews in the thread: https://www.homebrewtalk.com/f66/kona-fire-rock-pale-ale-ag-clone-52220/

The question i have is why, when going from AG->Extract do you get rid of the munich and honey malt and just use amber extract?

According to Briess's website, amber extract contains "Ingredients: Base Malt, Caramel Malt 60L, Munich Malt." So I guess the Munich malt is there.

But why not just stick to using pale/light extract, and adding munich/honey malt as a steeping grain?

Thanks!

Both of those malts need to be mashed. Simply steeping them may result in unwanted starch content.