Amazon Kindle eBooks: purchasing with a gift card

Sporadically I receive a gift card for participating in a survey, and recently I decided to purchased a Kindle eBook with this card. Once I was at the book's Web page on Amazon.com, I was only given the option of using the "Buy now with 1-Click©" button." This would apply this purchase to my credit card listed as my default payment option. I didn't want to do this.

I had Amazon help call me, and after 40 minutes with a courteous and kind rep, I had to end the call without resolution. But I did receive a very sincere email explaining a work around:

In this case, As you would use Visa Gift Cards to purchase Kindle books, What I suggest is, Whenever you get a Visa Gift Card, Don't add it to your Amazon account, But convert that Visa Gift Card into Amazon Gift Card balance by reloading your Amazon Gift Card here: https://www.amazon.com/asv/reload/order?_encoding=UTF8&ref_=asv_yab_reload_your_balance . Once money is reloaded from your Visa Gift Card to Amazon Gift Card, You can use the 1-Click to purchase your Kindle book and 1-Click will use the Gift Card balance. By this, you do not have to switch the default payment methods in 1-Click settings.

I've completely made the transition to buying mostly eBooks for several reasons: ability to highlight & annotate, not having the bulk and weight of paper books, etc. If I can't find a Kindle version of a book, I immediately check if a used copy is available.