The reason we chose to not go with a pay membership model for the Pro Club was frankly to keep matters a bit simpler both for us, and for customers. Just pay for what you want, whenever you want it, no strings attached :) This also frees up the developers in the Pro Club development group to be able to work more at their own pace, and not feel like they have to meet a production quota in fear we won't have enough in that area of the store every few days to meet the promises made in any sort of paid membership area.