So the coupon is currently not being applied at all until login. We’ve tested from different computers/IP addresses and using private browsing in both chrome and safari. The coupon does not apply until the user enters there email address during checkout. We want it to apply immediately so the user can see the discount prior to beginning the checkout process. The discount is what is going to help new users start the checkout process.
You can test using this link: http://unitedsteaks.com/?apply_coupon=firstorder10
Add a product greater than $50 but less than $150 to the cart, view your cart, and you can see that the coupon is not applied. But if you create an account, then use the link it works.