The article said the man died of natural causes, so its pretty clear they wanted to continue to receive his Soc. Sec. other benefits, and have access to his bank accounts, etc... as if he were still alive.
So go as far away as they can imagine to dump the body. For these two geniuses, it was Arkansas
No doubt they figured if they dumped the body somewhere in flyover country the hayseeds would never be able to trace the body back to someone who lived in NY.