Thank you for your comment. One trick that I have found is to use a WAON card with JAL credit card. My wife mentioned that if you charge your WAON card with JAL credit card and use it to make payments at MiniStop on specific dates like the 5th or 15th of the month, you can earn JAL mileage. The details are a bit complex and I'm not very familiar with them myself. However, I've been looking for bonus mileage offers when applying for credit cards, especially with AMEX for ANA mileage. It seems like there are quite a few options if you are living in the US.

Thank you,