"Membership Sites Are Stickier With A Membership Card!"
Most high end clubs will give you a unique membership card as a sign of your status.
Online memberships are no different and so are online customers.
By showing them an image of a card that represents your site you create trust in your customer's mind an that will really help you with your sales.
Also, your visitors will stay longer on your site and you will see an increase of your conversion ratios!