 Neither was the regulation faulted, nor could it be, on the ground that without overnight sleeping the plight of the homeless could not be communicated in other ways.The regulation otherwise left the demonstration intact, with its symbolic city, signs, and the presence of those who were willing to take their turns in a day-and-night vigil.Respondents do not suggest that there was, or is, any barrier to delivering to the media, or to the public by other means, the intended message concerning the plight of the homeless.