Forget about it. If the company wants a sick note, I'll provide a sick note. Even if I'm off a one day trip for a cold. If they want me to go to the doctor, and FedEx wants to pay the $200 doctor's visit charge, and whatever blood tests the doc might order up, even for a freaking cold, it's their money, they can spend it. I have no problem ponying up the $20 copay to avoid harassment. They want a doctor's note, they got it.
Though it's kind of embarrassing when the doctor laughs and says it's kind of weird that we're being treated like grade school kids. I can handle it.