For the past several years Amazon has offered a financial incentive to customers who chose the slowest shipping option. This one- or two-dollar credit could be used to buy books or ebooks, or instant videos.
I've never made use of the credit but with the latest change to the program I just might.
A reader has tipped me to the news that Amazon has once again increased the credit to $5.99, while at the same time the retailer has also restricted it so that it now only applies to items sold in Prime Pantry:
Prime Pantry is Amazon's program to get you to order consumable and comestibles. The selection is limited to more or less what you would find in a supermarket, and each order shipped in a standardized box with a flat $5.99 fee. Target offers a similar program.
The $5.99 credit is in fact not a new development but a periodic change that Amazon has made at least twice this year. This is the first I've noticed, but it has been noted on MobileRead that Amazon has offered this credit in March and in July of this year.
The $5.99 credit was subsequently replaced with the $1 credit, which means Amazon is offering both credits in rotation.