Certainly every point-of-sale has surveillance cameras and whether you pay cash or not, the federal government has very accurate records of every single item that you purchase. Be it a corn dog, a can of Dr. Pepper or women's lingerie that you plan to wear in private.
And voice recognition. And try to buy something at the hardware store, even with cash, and refuse to give them your phone number.
DEA regularly mines Americans' travel records to seize millions in cash
"It is a lucrative endeavor, and one that remains largely unknown outside the drug agency. DEA units assigned to patrol 15 of the nation’s busiest airports seized more than $209 million in cash from at least 5,200 people over the past decade after concluding the money was linked to drug trafficking, according to Justice Department records. Most of the money was passed on to local police departments that lend officers to assist the drug agency."
The problem here, is government. Become as independent as possible, while you still can, learn to work around the system. Learn and start using Crypto-currencies (to some extent), develop local networks of like minded individuals who will use cash, "junk silver" (in Venezuela 1 oz silver is now worth the equivalent of $2,000), barter, etc.
Our debt based, unchecked, financial fiat systems are going down word-wide, and soon. Get prepared for it now.