I was in a local comic shop a few years back purchasing the first Spirit Archives volume and a few issues of Kitchen Sink's now-defunct The Spirit: The New Adventures that I needed, and the kid behind the counter asked what "the big deal was about Eisner and The Spirit".
I replied, "Take a look around you, and then thank God for Eisner. He basically built the framework for the storytelling techniques present in nearly every book in here. He's possibly the reason why this shop is here, and why you have a job."