(mostly scrap yards) -- generally much less mass than a ship that is more seaworthy (a lot of early salvage happens before they get to the scrap shore, ships aren't fully loaded, look at their waterline in the videos). And most importantly much much less velocity (1/2mv^2 goes down rapidly with slower velocity). What is is truly impressive is that they estimate the mass, and know very closely what speed to get them too in order to solidly ground them without wasting a lot of energy getting them going faster than necessary.