At any liberal rally there are going to be communists, socialists, union members, teachers, anti-war protesters, hemp activists, eco-nuts, anarchists, etc. That's who is there. They normally show a mix on the news, but I don't see the need to show every flag or sign so that the viewer can decide. We know what's up already.
Really? The viewer knows what's up already? That is complete nonsense. And no one is asking them to "show every flag or sign," that is a straw man. The media is there (in theory) to cover the event in full. Not to pick and choose what to show. If there are Communists there openly and actively demonstrating, then that should absolutely be covered. Why on Earth would they not cover it? It actually portrays a false version of the event to not display the kinds of groups who are there OPENLY displaying extremist and radical political philosophies. To assume that the public simply knows already is a completely fallacious argument. The news coverage absolutely influences the way the public perceives the event and that is something that is not in question. Choosing not to display a radical group is to influence the way the public understands and perceives the event.
An exemplification of this notion is that the media will certainly jump on images at so called right wing "Tea Party" events that they can even remotely associate with political extremism. To imagine the argument of, "the media needn't cover inflammatory or politically radical symbolism at a right wing event since these elements will always flock there and the public knows what's up already" is simply incomprehensible. The very fact that they have shown extremely willing to stretch the portrayal of images of early American revolutionary symbols to illustrate a "radical" presence at these conservative rallies only further illustrates the hypocrisy of this line of thinking.
If there is an open and generally accepted presence of Communist imagery there, it should be covered appropriately and in it's proportional context, not hidden from the public in the coverage of the event lest the media be rightfully shown to be inconsistent and untrustworthy. Regardless of where one stands, intentional lack of coverage of these elements only serves to justify the distrust in the media that many have.