you've also got to factor in what works as ID in Britain, might not work in Argentina and vice versa. Then you've got the issue of what is deemed as acceptable in Argentina, isn't here. Look at the (fairly) recent meltdown because Cavani called his mate "negro". Term of endearment to him and everyone he knows (including the person he was talking to) but he's in Britain and folk just wouldn't accept his reasons for using the word. How can Facebook possibly know where to draw the line when every country has various levels of acceptance?
There's no easy answer. The authorities can't even really respond because loads of these accounts are based abroad (or so it would appear). Glen Kamara and Kemar Roofe recently had to go through daily abuse but all the accounts were Czech so Police Scotland couldn't rock up and lift them all and the Czech police couldn't care less.
I personally think (controversially perhaps?) that the best answer is to ignore. Do not draw attention, do not share, don't give them the time of day, delete, block. The vast majority wouldn't say boo to a goose, they're online attention seekers using shock tactics to get the attention of the target. Starve them off what they want.