That is a JW urban legend, but its somewhat close to my teenager years. I grew up in the city, and still reside in the city. Not exactly South Central Los Angeles but not quite the Suburbs either. Working class city, with spots of Middle class neighborhoods, Upper Class neighborhoods, and typical bad neighborhoods that are in every major city. I've been out of high school for well over a decade, so i don't know how Black youths are today when the Pledge is to be recited. Especially now since Obama got in, I wonder if the mood has softened. I'm somewhat out of touch nowadays, but back then.........the dudes I hanged with, would have no problem spitting on a flag, or burning a flag. They werent standing for the national anthem, and werent pledging allegiance to anything except their "hoods", or their flags, which was a hankerchief. So at the beginning of the school year, when it came time to stand for the Pledge of Allegiance, often times I was the only one who stood. I didnt cross my hand over my heart or anything, but to show respect I stood. Eventually the teachers give up after a few days of arguing with the other students, and as a result I didnt have to stand any more.
There's nothing wrong with standing to show respect. Pledging, or singing along is where the issue lies.