disk encryption; hidden containers

[Wojciech Puchar]

>> To locate them, all a cyrptanalyst has to do is to look out for
>> regions on the partition with very high entropy,
>
> The trick is to hide the volume somewhere that is legitimately filled
> with random numbers.
>
why hiding the ENCRYPTED partition at all? what's a problem someone else 
will know that it exist, being unable to read what's inside.