That is the AER's usual policy [1]; R&R's paper was published in the May issue (Papers and proceedings) which is for all intents and purposes a completely different and almost non-peer-reviewed journal [2]. I suspect (without any knowledge) that there will some pressure to distinguish the AER and the papers and proceedings more after this episode.

[1] http://www.aeaweb.org/aer/data.php [2] http://www.aeaweb.org/aer/pandp_faq.php