"So, who benefited from the sale of the marbles? The Greeks? The people who created them?"
Well, let's see shall we. It certainly was not Elgin, he lost a fortune on the sale. Can't be the people who created them, they were pretty old when they were sold and the creators were pushing upo the daisies by then.
The Greeks. Well, Yes! of course.If they had not been rescued by Elgin, the Greeks would not be benefitting from the exposure of their own culture that the display of these items shows.
But mainly, it is everyone who has benefitted - if Elgiin hadn't done what he did, they would not exist. Period.