I was replacing outlets in the basement and noticed that unfinished basements require them to be GFCI protected. While I did do this, I can't help but wonder: WHY?? I searched for the NEC definition of "unfinished basement" and I just don't see why the fact it's not "habitable" it needs GFCI. I can understand moisture areas like outlets near sinks, etc., but not this: my basement is very dry and whether the basement is finished or not does not affect the moisture content. Does the NEC explain this?
Even "dry" concrete contains considerable water, and is a relatively good conductor. So, it's a relatively good path to ground for a person touching it, increasing the odds of a lethal shock.
Generally, for something to make it into the electrical code, some number of people have probably died due to the lack of it before that happened.
You don't need GFCI receptacles anywhere. Nobody cares how you provision the GFCI protection. You are welcome to have one GFCI device and feed all the receptacles from the protected zone (LOAD) of that GFCI device. You should take the time to learn exactly how downline protection works, and then, put LOAD to good use! That will greatly reduce the cost of fitting GFCIs, since you then only need 1 per circuit.
It's really a statistical numbers game with the NFPA. They are looking at accident statistics and where accidents happen. It's not just the access to moisture-containing concrete and brick; it's also that the devices used in basements tend to be more risky equipment.
NFPA is now requiring GFCI and/or AFCI on pretty much every circuit, but the requirement for unfinished basements came in shortly after kitchens and bathrooms, i.e. high on their priority list. So it's pretty apparent this has been a problem area according to the statistics.
One thing you should do, if you have a freezer, refrigerator, fire alarm, radon system or other safety critical appliance, is talk to your AHJ (inspector) about a variance to exclude that appliance from GFCI. For pretty much all those systems, GFCI is completely useless because e.g. a refrigerator is grounded other ways, fire alarms and radon systems are hardwired and don't create particular shock risks, etc. The inspector will typically want to see a single, solitary receptacle (1-socket instead of 2-socket) and want it labeled "Refrigerator only". I for one prefer to put a regular 2-socket receptacle right next to it that is GFCI protected, so that no one is tempted to stick a 3-way splitter there or something.
Some basements are prone to flooding even if yours isn't. Plumbing is often run through basements which further increases the risk of a flood. If the outlets end up under water this isn't a good thing since water and electricity don't mix.
In this case, it's easier to apply a blanket rule to all basements in all areas than it is to regulate individual basements. Then people want to sue you because THEY did something stupid. It's better to be safe than sorry.
Partly because some unfinished basements have water containment risks, and the code is written to not create work for inspectors arguing the risk for each individual installation.
A Code-Making Panel document I saw a few of years indicated manufacturers were pushing to require GFCI protection for all circuits. The code making panel was pushing back only sightly, by adopting their proposal incrementally, by locations of highest risk first.
It does seem like could be a case of a manufacturer identifying how they can use government regulation to increase sales, and the willingness of government to use all the power of regulation that the govern don't protest against.
There are many manufacturer representatives in code making panel and I believe there is push towards Increasing the sales. Remember back in 1999 consultants alarmed everyone about Y2K problems and received lucrative contracts to solve problems those were not existed. I still keep the book telling “Airplanes will fall of sky, because their clocks will fail in control software when midnight new year 2000 arrives.”. None of proven theories happened. Now the sales focus on Internet of the things (IoT), in industrial process it is IIoT. Process industries will need billions of sensors and switch to complete digital control to be competitive. Some Dishonest Sales people will never stop exaggerating.