Julep's Day 6 Promo Is Better Than I Think It's SUPPOSED To Be!

So as expected I woke up today to an email from Julep for the daily installment of their 12 days of giving. I actually thought this would be a good one to get (I knew my girlfriend wanted a specific colour) and I had 3 from December on my wishlist that I had not yet gotten. Little did I know just how good a deal it would be..

So I put four colours in my basket (not these four, this was just an example after the fact) and when I put in the discount I paid and thought nothing of it. Then I did a double take is this SUPPOSED to be how it works? Is it supposed to be $14 off each duo even if you paid $11.20 each? It worked out to be $4.20 a polish instead of $7 a polish!!