On WWJ radio, I heard that the crowds were larger than usual, in part because it might be the last time Detroit holds this fireworks show unless the suburbs pitch in. The same could be true of the Thanksgiving Day parade, the one that displaced Occupy Detroit. The people being interviewed on the radio thought that would be a shame.
Based on what I think motivates Americans to act and the presence of the Michigan State Police and Wayne County Sheriffs at the show, I'm sure that the fireworks and parade will continue. People want their entertainment, especially if it comes in the form of an annual civic ritual to celebrate the seasons, and messing with America's entertainment is the one guaranteed thing that will get Americans to act.