Related question from my previous post - wasn't sure it was worth a separate thread ...
A recent Amex Blue Cash Preferred Terms and Conditions update taking effect July 01 2017 states specifically that Gift Card Purchases and Reloads (and other "money equivalent" transactions) do not qualify for the normal 6% rewards for supermarket spend.
Can Amex really identify whether I'm buying a GC at the local store vs. groceries? Is there any way to avoid scrutiny other than avoid "obvious" purchase totals like $505.95?