(CNN) -- Not since that cranky old lady asked "where's the beef?" has a fast food chain had an ad as funny as the Chick-fil-A cows begging people to "Eat Mor Chikin." And when I moved to Atlanta, where the franchise company is based, I did. Then I found out the company was funneling portions of its proceeds to fight gay rights. Now I'm back to eating chicken, and not chikin. This is the U. S. Constitution at work -- freedom of speech meets freedom of expression. Chicago's mayor Rahm Emanuel, Boston's Thomas Menino and a handful of other mayors threatening to ban Chick-fil-A because of anti-gay marriage remarks made by its president, Dan Cathy? Not so much.
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LZ Granderson: I was a Chick-fil-A fan until I heard of its stance on gay rights
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He says the Constitution doesn't allow mayors to ban Chick-fil-A based on its president's views
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The Constitution does permit people to peacefully protest, he says
Rahm and @placeholder making out with each other in protest.