Real research, on things like game theory, actually has shown how a single signal can have multiple functions that vary depending on the context. This "research" is clearly not aware of these modern advances...
Uh, and the funniest thing is that the only article in the "Journal Of Pragmatics" that I could find said just the opposite: "Humor serves a wide range of functions at work, one of which is to foster collegiality. An analysis of interactions in New Zealand workplaces showed that one of the most important functions of humor was the construction and maintenance of good relations with fellow workers. " ( http://www.sciencedirect.com/science?_ob=ArticleURL&_udi... )
One of the key ways of creating the hierarchy is to feed the alpha dog first, and only feed the other dogs when the alpha dog is done. This is of course not the only way to create a hierarchy, and as you point out one would exist even if food was so abundant that it wasn't an issue.
The order in which the food is eaten is simply a reflection of the hierarchy. One eats first because one is the king. One does not become the king by eating first.
Same with humor. Review the material on the use of pornography and humor in the French Revolution.
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So you're saying that the hierarchy would not exist except for the food? The OP's post said that humor, like food, _reflects_ an existing hierarchy, and, as far as I can see, this dinner table hierarchy would exist regardless of the food.