I have had a look at this post about geohashes. According to the author, the final step in calculating the hash is interleaving the x and y index values. But is this really necessary? Is there a proper reason not to just concatenate these values, as long as the hash table is built according to that altered indexing rule?
From the wiki page
Geohashes offer properties like arbitrary precision and the possibility of gradually removing characters from the end of the code to reduce its size (and gradually lose precision).
If you simply concatenated x and y coordinates, then users would have to take a lot more care when trying to reduce precision by being careful to remove exactly the right number of characters from both the x and y coordinate.