Some people have been known to come to the store just to take a picture as a memento. Apple employees have been known to transfer to the Glendale store because of its hallowed status, and some customers say that the level of expertise of the staff surpasses other Apple stores.
Some think that the Glendale Galleria is a horribly run-down mall. This doesn't seem to bother those in the know who frequently stop by. It also doesn't bother Apple for that matter, since it's located close to several major Los Angeles freeways and brings in a good number of shoppers.
As with most things Apple, this is not without controversy. Another Apple store in the much higher-end Tysons Corner Mall in McLean, VA, opened the same day (and several hours earlier), but sadly did not attain the designation of retail store 001, so it can't claim the number one spot.