Typically Israel bars all media from IDF activity. The prefer to operate under cover of media blackouts. In this case, calling for a media blackout was a little too obvious. The usual deterrent used against "uncontrolled" media is to shoot a couple of them and let the rest take notice. I am sure that all the various media personnel on the flotilla know that they take their lives in their hands when they annoy Israel.
Three Palestinian teens killed by Israeli army fire during protests near Gaza border (Haaretz)