Dean Martin did advertising for various companies over the years. It was a win-win situation for both Dino and these companies. Any business would have been wise to hire the King of Cool to pitch their products. They were sure to bring in plenty of Dino fans, who would buy their product or use their service because Dino recommended it. Plus I'm sure Dino enjoyed the money and other perks that he received for these endorsements deals.
This picture comes courtesy of my pallie Timmy.