Retirede,
The cost to recharge a suppression system is roughly $20/cubic foot of protected space (not including labor). For large data centers this can have a significant impact especially if someone accidently discharges the system.
Some end users are apprehensive to to put pipe, filled with water or may be filled with water (pre-action) above their data centers. Others take into account the cost of equipment damaged by water and the replacement cost of that equipment as well as the "down time" cost. New construction often doesn't care about the the long term cost of ownership, unless the owner is intimately involved in the construction, and suppression systems are often considered a Capital Expenditure. For the building contractor, it's all about the initial cost of construction.
Small data centers often do have gaseous suppression systems, but industrial area (which is what this is) they will often have a water based system. I asked about data centers because this would likely be the only space where someone might have rules regarding the area changing from a Dry location to Damp or Wet location.
In any case, I have an inspector that needs to be educated/challenged on his decisions and so far he's failed to justify his requirement. Rather than arguing with him, I always play dumb and say "...well, isn't that interesting...to educate myself, can you tell me where this is written in the codes?"