Southwest Airlines uses some creative communications to re-enforce the value they deliver to their customers.

Like this “thank you” message that came via a confirmation email, with a call to action to tell them about your trip in their online Travel Guide.

And then there is this banner, which appears onscreen after a purchase.  It re-enforces that Southwest Airlines does not charge for checked baggage (well,  your first two bags within the weight and size limitations).

Messages like these are important.  It is far too easy to forget to remind customers why they do business with you.  Every chance you get to need to communicate (over and over again) the value you are providing customers.