Hi,
I have a question, how should I understand:
And, while you can register and play on multiple Accounts, you are not allowed to have more than three (3) Accounts with Battle.net Balance.
Do credit card transactions not count towards Battle.net Balance or does every in-store payment count as a battle.net balance?
Battle.net balance is the currency which is, for example, shown in the upper right corner of your account overview [https://account.battle.net/overview].
You have to actively buy it in the shop [https://eu.shop.battle.net/en-gb/product/balance], claim a code on a code card (available in physical stores) or use a WoW token bought in the auction house.
If you are using a credit card to pay your WoW subscription, this doesn’t generate any Battle.net balance.