WHEN something like that happens, it can happen on any part of that continuous long stretch of beach in the Zona Sul. And it (a newsworthy arrastao) has shock value, but is not a daily or weekly or even monthly occurrence at a given Posto by any means. Of course you have to be careful of whatever (minimal stuff--if you don't bring it, it can't get stolen) you bring to the beach, but you don't need much and the hotel areas are staffed so you are not an island of a sitting duck alone on the sand.
Once again, no need to scare the newbies with stuff that is not likely to happen to them on a fairly short visit to Rio.