In the past four years, the price of used grease has gone from nothing to 38 cents a pound, the New York Post reported Saturday.
Now, thieves are stealing the stuff from restaurants and other businesses to cash in.
"It's really crazy out here with this grease," said Eddie, a truck driver who picks up used oil in Brooklyn. "I went to one of my stops, and I actually saw a guy pumping grease out with a vacuum cleaner."
Edward Gunderson, president of M&E Soap, said his company, which buys food oil in Brooklyn and Staten Island, had been broken into several times since the first of the year.
"It's an easy way to make a buck," Gunderson said. "They can walk out with $200, $300 or $500 worth of material."