I grew up with a guy and worked at the same company with him. I truly don't remember him ever buying very many groceries. Now keep in mind this was about 30 years ago
before cameras became in widespread use.
This dude would go to Chili's, Bennigan's, Applebee's, TGI Friday's and other places, be seated, order his meal, eat most of it, and ask for the remainder to be put in a "doggie bag" to be taken home.
As soon as the waiter went to the kitchen, he simply walked out without paying.
McDonald's was also a favorite mark of his. He would hit a drive-thru, time it right, and pull in front of a car who was paying for their food, pull up to the next window, grab "his" food, and drive off.
I know this to be true because he lived next door to me in the same duplex.
He never got caught.