Also, they didn't want you to be able to guesstimate how many machines / computing power they had, for similar reasons.
People complain about new data center slurping up all local water and then neither Google nor representatives can say "No, actually we're not, here is the numbers", because Google doesn't want their competitors to guess how many machines they have in one of their data center? I'm sorry but that sounds very far-fetched, must be another reason parent wrote it was "obvious" they couldn't divulge how little/much water the place uses.
They published a lot of less specific info (PUE numbers, water efficiency, etc)
They were very sensitive about any site specific numbers.