David referred a friend to DirecTV. The satellite provider has a pretty neat referral program, promising a discount to both the new customer and the person who referred them to DirecTV. Well, theoretically. David writes that he and his friend learned that in order to get their referral discounts, the new customer has to either sign up on the Web or call a special number. He didn’t know this, and now neither he nor his friend will get their discounts.