I thought it was disrespectful, as the Games are supposed to transcend politics. I felt if they wanted to protest what was going on in the United States at the time, they could have chosen a more appropriate way to do it.
For example, in the very same Olympics, Vera Caslavska, a Czechoslovakian gymnast, protested the Soviet invasion of her country (which occurred months before the Games started) by quietly turning her head during the Soviet anthem. No obnoxious display, just quiet protest. If you're going to make a statement, make one with dignity.