Apple has a new way to load up your iTunes account with funds, and it makes use of Passbook – just hit the “Redeem” button in the iTunes Store and when you’re in an Apple Retail location, you can call up your iTunes Pass in Passbook and an Apple sales associate can scan it, take a payment via card or cash, and your iTunes balance will be updated right away. The feature debuted originally in Japan, but has begun rolling out to more and more countries, and now appears on the U.S.-based Apple iTunes homepage.

The feature is a key one for Apple’s ability to reach an even wider range of customers with its digital content stores – enabling a simpler method for iTunes account top-ups means that the company can better serve its customers who either aren’t able or don’t want to use credit cards to automatically transfer funds to their account. Kids who don’t yet have credit but earn their own cash through part-time jobs or allowances are one example of this type of customer, but also customers in markets like China who might not have as ready access to credit as consumers do in the U.S.

Users could already set up an iTunes allowance for their kids, or fill up their account credit using physical gift cards available in many retail channels, but the new iTunes Pass option is just one more way Apple can make the process easier, which in the end means more money in the coffers and an even better iTunes digital goods economy for app developers and content providers. Plus, rumors persist that Apple could eventually make a broader play for iTunes-powered mobile payments, and this ability to reload would definitely help with that.