What are your thoughts on this?

My son, who is six years old, has a list of chores that he can do throughout the week. Each task accomplished earns him a certain amount of money, or allowance. At the end of the week, on Friday, the money he has earned goes onto a prepaid Visa card, which he uses to buy games, music, or whatever on his Xbox or tablet. He gets paid, which he loves, and he has a payday. He loves this. He can spend it, or he can save it. What do you think about it?