PS3 limitations was the reason behind the reused assets in the seamless zones, to where they wanted to load areas fast and seamless, but had to reuse the same grass and rocks, or something like that. Hence the copy-paste.
They got around this to destroying the seamless-ness to back to FFXI-like split zones for ARR. Different graphics were loaded for the different areas, the areas were broken up into smaller areas, and the PS3 limitations were averted.
Edited, Dec 10th 2012 1:51am by UltKnightGrover