It requires a degree of confidence to sing in public, as part of a crowd, effectively and in tune.

I do it more than most, but I still often experience a degree of repression (or something like that) that closes the throat and makes it difficult to hit notes. I think most folks who have that experience "take a hint" and shut up, while those of us who are reluctant to be denied a chance to sing out will make an effort to overcome the initial stiffness and get it on.

Martin's right ~ much of the small amount of group singing that occurs in mainstream America takes place in houses of worship. As corrollary, I would point out that some musical events serve a similar purpose for members of society who don't attend church, or at least for groups that don't all attend the same church together ~ case in point, the communal celebrations centered around the late great Grateful Dead. Certainly, the currently ongoing Jazz & Heritage Festival serves a similar purpose for some of us here in New Orleans, and I'm sure that other local/regional communities have similar celebrations with similarly spiritual communal-singing activities.

Burke: The Cajun Grocer ad is nowhere to be seen now that I'm back on this thread, nd I don't know anything about that business. Those ads change all the time; right now I'm looking at an ad for Cafe du Monde Beignet mix, which is undeniably authentic (sold by the actual purveyor of beignets on Decatur Street across from Jackson Square), but I would not be so sure that what you make at home from the mix will match up to what comes out of the CDM's own deep-fryers.