What about them? They must adhere to hours of service no matter what they drive just like everyone else. It's not about what license you have in your wallet. It's about safety. And medical cards don't impart something magical. They're about showing the driver is being monitored regularly to insure he doesn't have a condition that might endanger himself or others while driving a heavy commercial vehicle. Once a doctor determined my blood sugar was out of control I was required to get it under control in a very short period of time before allowing me to drive again. Once that happened he gave me a 6 month card. I had a one year card. Diabetics can have strokes or pass out if their blood sugar remains high for a long time. Drivers of big rigs have killed people after their diabetes caused them to pass out. Also diabetic neuropathy in feet makes it difficult to feel fuel and brake pedals. You're getting hung up in the weeds about cards but it's about driving heavier vehicles and public safety. There's an agency that monitors driver compliance with DOT physical recommendations. It's reported to them by the company if a driver passes his physical and got a two year card or if the doctor recommended shorter intervals for physicals and why, or if the doctor failed the driver. They send a form to the driver's mgr and require the driver take that form to the doctor who answer questions. I know because I experienced it. Yes there are people who cheat the system but they're in serious trouble if they have a medical emergency while driving and are found out. But in the case of FedEx no sane mgr is going to put his job on the line covering for an unhealthy courier. So they have a very clear process they follow.