In this ad for Camel filters, effeminate-looking men are placed in direct opposition to a "real" man, the kind of man who ought to smoke Camel Filters.
The ad reads "With every pair of Mr. Stanley's hot pants goes a free pack of short-short filter cigarettes. Now everybody will be smoking short-short filter cigarettes...almost everybody." Under the last two words is a picture of a traditionally masculine man whose rugged attractiveness is to be accentuated by his cigarette, which rests between his lips.
Beneath the pictures the page reads "Camel Filters. They're not for everybody. (But then, they don't try to be.)"
This ad is problematic on a few levels. First, it outright says Camel Filters are not for effeminate men. Secondly, it inherently implies that such men are laughable, trying on silly clothes and sporting goofy expressions. This exists in opposition to the picture of the conventionally attractive, too-cool, masculine man who wouldn't have the time for such silliness. In fact, he doesn't even have the time to acknowledge the camera taking his picture.
The discrimination in this ad, under the guise of humor, is as simple as "this man is better than those men." These presumably gay men are pitted against the societal standards from which they've deviated and the audience is asked to make a choice that is essentially "Who would you rather be? We thought so. Smoke Camel Filters. "