- Maybe cost including shipping fee will be lower than you used to buy. (Bulk buying will be more beneficial)
- Probably fresh than buying locally.
- In some case you can buy clearance sale or close expiration in low price.
Here below shop on Rakuten Global ships overseas.
http://domoarigatojapan.weebly.com/blog/how-to-buy-on-amazoncojp-how-to-register.
Or first time to Rakuten Global refer
http://domoarigatojapan.weebly.com/blog/how-to-use-rakuten-global-service
But maybe not needed because it's easy to do.