Some really great points being made here.  
From a marketing standpoint- shoppers like to do business with a company that rewards them for doing business - such as frequent shopper points. They also like a more personalized service. I would suggest using sales information to try and offer a rewards program for your repeat consumers. To enhance their shopping experience with your company. For instance, if you have people who return to shop for thinking of you cards and buy several varieties- send email offers and offer a package deal on a certain number of cards- or so much off each card with their return visit.  
Also, HallMark and other companies spend a great deal of time, effort & money to build an image so that people are not just purchasing a card, they are purchasing the package- the image that comes with purchasing a card there. They also send special offers and savings for their repeat customers based on previous purchases. Unfortunately their image doesn't always carry over into customer service & satisfaction which has cost them business & allowed for other card companies to come into play. Building and maintaining a customer base is crucial in today's global market & in future business transactions- if that area is lacking- customers don't feel special or like they are being taken care of- so they go elsewhere, no matter how great the merchandise is.  
At this point in the game for GCU, I believe the key to larger future sales is to concentrate on the number of customers you see returning and trying to enhance their shopping experience. When you do this, they will help build your customer base for you. It is all about making them feel like part of your family here at GCU, that little something extra that they can find here and no place else. It is sort of giving them that "Cheers" concept- where everybody knows their name when they walk through the door at GCU. If you can give customers that sort of feeling to a certain degree- that will build sales more than any advertisiement you could spend money on. We are truly a melting pot of personalities here, and the diverse atomosphere is half of what makes GCU so fun- at least for me. At any rate, these are a few of my thoughts on the subject. It is kind of basic marketing information, but it makes great sense!