$400 is pretty close to the cost of an office visit, physical exam, metabolic panel, lipid panel, and EKG, which is what a primary care doc is going to order annually on something like 90% of Americans after a certain age.
It shifts the expense of routine care and checkups to the patient. If you view insurance as indemnification against unexpected loss, it shouldn't be paying for expected, routine costs.
That's also why car insurance pays you to install LoJack and homeowners insurance pays you to install fire alarms.
But this isn't true -- at least for any car insurance or homeowners insurance that I've purchased. You often receive a small discount, but the discount alone doesn't cover the cost of purchase/maintenance.
A health insurance analogy would be: Customer A pays $100/mo because he gets an annual checkup and takes the medicines the doctor prescribes. Customer B pays $200/mo because he hasn't seen a doctor since college.
Customer B could reduce his total out of pocket by $800 per year if he paid for the $400 visit.