Some applications have the need to create IDs in a distributed manner, eg. Og clients, and use that identity before the database returns it. These systems benef

Some applications have the need to create IDs in a distributed manner, eg. Og clients, and use that identity before the database returns it. These systems benefit from randomly generated IDs. You could potentially hist use a random number between 0 and 2^128-1 and still use ints, though I haven't seen that in action, usually pk with ints are centrally generated and consequitive.