Battle.net has to be the stupidest platform when it comes to adding credit to your account

Traded some games in at GameStop to get a $20 Battle.net card so I can get MW2 at a "discount". Well, in order to purchase a game through the website or the game launcher, you have to have the total value from one payment method. You can't split it. You know, like most other platforms that allow you to use a gift card and your debit card together because the year is 20-fricking-22.

So, what do I do? I go to purchase a Battle.net balance that will cover the rest of the cost for CoD. I get told that it usually takes 10 minutes for it show up on my account which is also stupid in and of itself. Well, here it is, almost 4 hours later and I still don't see an updated balance to my account.

I go off to do some research on the Battle.net site and see that it could take 24 hours for it to show up in my account. I facepalm and go back to the launcher to double check the price of the game with taxes. It is now $2 more than it said before, and now I have to add another balance and wait another 10 minutes to 24 hours. How does any of this make since to Blizzard?