The Pentagram is a symbol of a star encased in a circle. Always with 5 points (one pointing upward), each has its own meaning. The upward point of the star is representative of the spirit. The other four points all represent an element; earth, air, fire, and water.
There are two kinds of membership. The Goldstar membership costs $50 per year and you get the privilege of shopping at Costco. The Executive membership costs $100 and you get 2% reward on most purchases in addition. The price of membership is going up in 2012 to $55 and $110, respectively.
This keeps Costco strong. Costco does offer low prices, and joining, especially paying for the Executive Membership, is a good way to save money for many people. Once the chain has a customer, it's likely to hold onto him or her, because of the promise of what it offers, and the increased future savings it represents.