The backstory on his deal with Salton (the inventors and manufacturers of the grills) is that when he first made that return to pro boxing, George was tipping the scales at at least 325. Losing to Ali in "The Rumble" was devastating. He eventually found God and he read the Bible and the law at home. George also found hamburgers and barbecue and mac & cheese. People should have known he was a different man now, he didn't have a manager any more. He managed his own career. Don King had fucked him over.
But he tried EVERYTHING but did not lose weight until a little white female nutritionist figured it out: diet. She sat him down and learned that when he was growing up, he only ate meat on Sunday - his mom was too poor. He went to the Olympics with food packed by his mom, with no meat. The nutritionist made one change - she got him to buy a Weber gas grill and that's where Mrs Foreman cooked. His weight went down. George was still big, but he was fit.
Meantime, Salton created its grill and needed a spokesperson. They tried everyone, including O.J. Simpson who was having success with Hertz. They send him a prototype and he realizes that his gas grill was the same thing - let the oil fall away. George gets the invite and he goes to the meeting, very, very high up in the World Trade Center and walks into the room - by himself - and sees a big table with at least a dozen lawyers. He said they looked like sharks, "and started circling like them too...". They asked where his lawyer was and laughed out loud at him when he said he did not need one. George says "nobody can sell your product like I can - because I am a believer, it worked for me..."
When they demanded that he get a lawyer and also talked down to him, George got up, closed his briefcase and walked out. When he was about to get in his limo, someone tapped him on the shoulder, "they want you to come back upstairs.."
The original deal is not known, but for a decade, George was taking in a minimum of $4 million a month. Eventually, they re-negotiatied and he got them to buy his name forever for $150 million outright and a percentage of the company.
Rest easy, Champ.