Originally Posted by
krazykanuck
There are plenty of DPs in the Amex forum that Delta gift cards purchased from the desktop site trigger the Amex incidental credit while the mobile cstar ones do not.
With how wide ranging and easy to redeem the CSR travel credit is, I always find it a bit surprising people resort to buying gift cards, but it should still work if you use the desktop site.
This. (Or why people who don't travel much pay to use a travel rewards credit card.)