I think ingredients training would be a good place to start, even if it's nothing more than plastics cups of pale malt, dark malt, and a couple of types of hops. Then link this to how it affects the finished product.
If the aim is to encourage them to be advocates for craft beer in a situation where both kinds are available then this alone won't be enough. You'd need to have them automatically asking punters who want macro beer if they'd like to try the craft alternative, and that's only going to work when there's time for it. Certainly anyone who pauses for more than a milisecond at the bar before ordering should be greeted with a "Would you like to try a handcrafted beer?"