"Since I object to general surveillance, I use cash for ordinary retail purchases. I use a credit card only in the situations where I am forced to disclose my identity anyway: car rental, airplane tickets, and hotels."
"If you buy by credit card, companies and governments can monitor what you buy, too. So I buy things with cash. If the business says 'no cash', say 'no sale'.
http://stallman.org/archives/2003-sep-dec.html
"If you buy by credit card, companies and governments can monitor what you buy, too. So I buy things with cash. If the business says 'no cash', say 'no sale'.
http://stallman.org/archives/2010-nov-feb.html
"I never use self-checkout machines unless a store gives me no choice..."
http://stallman.org/archives/2011-nov-feb.html