Self-Checkout Express Lines

I go through the self-checkout lines at grocery stores to save time. When I have to wait behind some slowbie who scans their groceries as delicately as if they were buying a cart load of Fabergé eggs, I tend to get a little annoyed.

You know how most people have those value cards on their keychains? Since they already store information about what you buy, they should also be able to calculate your average number of item scans per minute at the self-checkout. People with higher scan averages should be able to access fast lanes so they don't have to deal with the amateur grocery store customers.