Because i heard that if you take it there, something will happen, like when it transfers you to a different time in HeartGold and SoulSilver.
If you take the GS ball event Celebi to the shrine in HG/SS you get to go back in time and fight Giovanni. The abundant shrine is where if you have both Thunderus and Tornadus you will see a couple of kids arguing then leave then a girl with tell you about Landorus then you will be-able to catch Landorus. The event Celebi that you transfer to B/W can interact with the Zora in the Gamefreak building and you can catch it the Zora.