Storage is never free
Especially in an enterprise environment.
With terabyte disks available now (generally speaking - the tsunami effect will not last), one would think that all IT departments have stuffed their servers with disk space.
That is not true, unfortunately. For some strange reason, enterprise servers are still quite often choking from mailbox mismanagement and small disk sizes.
Must have something to do with the fact that server-grade disks are held to much higher reliability and I/O throughput than basic consumer disks and thus more expensive in cost per GB.
That, plus the fact that IT is still viewed as a cost center, makes enterprise servers the red-headed stepchild in disk space availability.
On my personal PC, I have no less than 2 disks with 2TB each, plus four other disks for a total of over 5TB of storage space.
I know for a fact that there are a few companies not far from where I live that employ several hundred people and they have far less storage available on their mail server (think 300GB max).
But my disks are not RAID, or SCSI, nor are they high-throughput parity-checking error-correcting disks. They are just high-capacity consumer-grade disks and I was crazy enough to buy that kind of storage for myself.
My money, my choice. Company IT departments do not have that kind of freedom.