Its A Psychological Fact:

Using cartoon characters in cigarette advertising attracts young smokers! I remember reading an article that detailed how, after the introduction of the Joe Camel character, teens started smoking Camels like crazy - a brand they had typically ignored.
But Joe was hardly the first Camels cartoon character. Back in 1955 Camels added these cartoon headers to their long-running series of "famous-people-who-smoke-Camels" ads.Whether this was actually a marketing strategy to attract young people to the brand is open to debate - but I doubt that was the case. Cartoon characters were being used for a great variety of adult-targeted products (much more so than they are today) and the Camels people probably thought these clever and colourful cartoons would contemporize their ads.There was certainly nothing appealing to youths about the old fogeys and generally grown up people featured in the much larger photo/endorsement section of the ads.

What I love about these Camels cartoons is the "radical" quality of the irate person who needs a good smoke: they really remind me of the work of retro-illustrator extraordinaire, Mitch O'Connell's work. If you want a closer look at all these ads, go to my Smoking Flickr set.