This site is poorly designed; I didn't understand how the checkout form works. It appears at first that I'd have to enter a coupon code from somewhere to buy it

This site is poorly designed; I didn't understand how the checkout form works. It appears at first that I'd have to enter a coupon code from somewhere to buy it; I thought maybe from the Mac App Store or something, but that wouldn't make sense. It was only after thinking for a while that I figured the coupon code wasn't necessary to click the Checkout button.