Bit of an over statement. I’ve had a charge card since the early 1980s and was most certainly not a member of an any small club of “affluent customers.” then. I am not today, as well. That said, I’ve never used a credit card at a fast food joint.
“When I opened my first store in 1994, cash was king and “charge cards,” as they then were called, were status symbols held by a tiny number of affluent customers.”
I noticed that "affluent customers" too. I had credit cards in the 60s and as a G.I., I was hardly "affluent". I had two gas station cards and an AMEX.