If you are standing on your porch, you are on private property. If you are standing in a yard that is fenced, there is a clear division between private and public property, and you are on private property. If you are in an unfenced yard, and you are either the homeowner or have express permission to be there from the homeowner, you are on private property. In those cases, you may be able to make a good case argument the laws should not apply to you. However, if you are on public property or you are trespassing on private property, even behind the barricade that separates you from the floats, you are both "at" and "in" the parade. The fact that you are there indicates you are participating in the parade, even if you are standing there letting beads bounce off your face.