Do "Flood the Zone" Police Tactics Actually Enable Looting in Large Cities?

I'm not asking a question I know or even expect a particular answer to. It's a genuine question. We've all by now experienced or seen images of massed police - sometimes seemingly 70, 80 deep - "facing off" against massed protesters. Or, massed or semi-massed police converging on an area in rapid speed, or engaged in kettling operations that flank and enclose protest crowds. I won't pretend to know about policing tactics. It does seem to me, however, that massing police in this manner is not the ordinary course of policing large urban areas, and that police are thereby spread thin, as it were. This would be especially the case for opportunistic looters who are going to go where the police aren't. There was some discussion of this when the Loop got completely shredded in Chicago on Saturday, and certainly it seemed to be the looters' tactic in Manhattan yesterday.

Is it possible that one factor contributing to the widespread, devastating looting is that police tactics are particularly ill-equipped to handle large protests, and that the current "flood the zone" and "massed police" tactics are deeply counter-productive?