difficulty – Why does the Genesis block appear to have a lower hash than necessary?

The hash of the genesis block of bitcoin has two extra 0 as compared to other block hashes. According to the logic, it should have been the same as they all have the same difficulty. Why is it so? Was any special reason for doing so?

Hash of genesis block :
000000000019d6689c085ae165831e934ff763ae46a2a6c172b3f1b60a8ce26f

Hash of block 1 :
00000000839a8e6886ab5951d76f411475428afc90947ee320161bbf18eb6048

Hash of block 2 :
000000006a625f06636b8bb6ac7b960a8d03705d1ace08b1a19da3fdcc99ddbd