There are a lot of ways to earn miles. A number of years ago I did this. You buy a Safeway gift card with an American Express card and then use the gift card to buy a money order. It worked at some Safeways and at others it would not. Bottom line, it was not worth the hassle.
Alright, I've read through many of the threads here and have maxed out LSC and have ordered everything available from the mint. I'm in STL andnit near an AMEX office to get TCs. Any other ideas?