Marketing ploy? For a movie that cost 40 mill to make and was easily expected to at least triple that from the box office alone? Sony pictures brings in an estimated 7 BILLION a year. They don't need to create huge marketing ploys in order to milk an extra 10 mill or w/e.
If the hack, that was far more damaging and widespread than just the release of a movie, hadn't occurred, the movie would have been released as scheduled.
It's nothing more than damage control from the huge amount of backlash they've received, including the White house. They made a mistake, now they are attempting to correct it. Anyone who thinks it's a "marketing Ploy" is simply ignoring the facts of the entire matter.