Abraham was alleged to be from there, so why is it supposed to be odd that the founder of the Jewish tribes would have the same history? Is this some sort of retarded stoner argument that Judaism's version is fake because it isn't made up entirely different from the alleged Sumerian versions??? lol in order to be genuine they're required to make up an entirely different history??? Just stick with hitting the bong, and leave the attempts at logic to others.
In any case, it's entirely an allegorical lesson, whether 'Sumerian' or not, no evidence whatsoever the stories originated with Sumerians in the first place, and its meanings are multiple and rather sophisticated lead ins to even more complexities. And, Abraham didn't come from Ur, he came from a region in what is now southeastern Turkey; the assumption he came from the East, the Babylonian region, is a left over and incorrect assumption made by the discoverer of the ruins of Ur making bombastic, self-promoting claims that had no real basis in fact, but sounded great in the papers, and it's the story that stuck in the public imagination, despite what the OT says about where he came from, which was from the north. For the geographically challenged, Sumeria, Ur, and Babylon are east of Judah.