Why is everything a capacitor?
Capacitor (when pronounced "cuh-pack-itter") is more fun to say.
Personally I don't understand why it's not a violation of some electrical standard.
This comment and another one or two about UL (which is a company that famously wrote several standards in the US and now their name is still on them even though they're committee-written by members of various companies and you don't have to go to UL the company to do "UL" testing...similar to CSA being the Canadian Standards Association being a company you can have do your testing and their name is on the standards, but you can go to UL, Intertek/ETL, TUV-SUD, etc. to do the actual tests) make me want to put some information out there.
UL Safety standards in the US usually only care about what they consider "hazardous" voltages. They define that as anything at or above 30Vrms/42.4Vpk for AC voltages and 60VDC (for dry location use products...it's 16Vrms/35VDC for wet locations). So for 12VDC, they don't even consider it hazardous. There are other requirements for temperature of touch-points, but that gets much deeper and you'd have to find an applicable standard for this application. The way the standards generally operate, most individual items are tested independently, like the power supplies are tested to IEC 62368-1, which is a global harmonized standard that has replaced US standard UL 60950-1. They would test with general loads, not in a system. The cables that come with the supply are likely not even tested with it, but the supply would be hooked up to some general test equipment that simulates loading. There would be requirements on flammability ratings for the connectors and wires, but it's not a quality control standard either, so it isn't going to force any kind of manufacturing standards on the connectors and cables in question.
Also, the United States doesn't enforce any UL standards testing. The closest thing I've seen to that is an OSHA rule that says if you're a business and you're going to make your employees use a piece of equipment, it has to be certified to the applicable safety standard by an NRTL (Nationally Recognized Test Lab). Most companies don't follow this rule, but some big companies (like META oddly enough) get audited so when they buy equipment to run their Oculus hardware or other stuff, they make sure it's UL-standard tested.
Other countries, like those in EU have laws about testing all products on the market. They have the CE system in Europe and there are directives with standards in them that are intended to test all things. They would also use the IEC 62368-1 standard as IEC is an international electrical equipment certification body that most of the world uses for standards. Most current UL/CSA standards are now harmonized with the IEC standards for example. CE gets a little more interesting because you'd have a standard for every component, and a standard for systems if they're sold that way. So the power supply would be tested, and if Dell (for example) wanted to sell a computer in Europe, that computer should also be tested to an applicable standard (I'm not sure what that standard would be). I personally test a lot of systems to IEC 61010-1, which is "Safety requirements for electrical equipment for measurement, control, and laboratory use". Depending on the customer, I could test a computer to that standard. The difference with the NRTL OSHA requirement above and CE is that CE is a self-declaration (for most markets, not medical, fire alarms, etc.) which means a power supply company can do their own testing (which is still supposed to be to the correct standard), publish their own report, and make their own declaration of conformity. That's the standard practice for safety standards. I've seen bulk DC power supplies from big industrial companies (that take universal AC-input and output 12VDC anywhere from 30-1000W) have their own safety report that they generated that was lacking any kind of clarity on what they actually tested or how but more of a "oh yeah, we definitely did this test, trust us, *wink wink*". I've seen a simple piece of equipment sold to optical labs that had no safety standards applicable to it because it just ran on USB power, but it was supposed to be tested to EMC directive standards for noise immunity...when I asked them for their report, they sent me a declaration of conformity...the standard they listed was for "electric griddles and griddle grills". I was like "you googled 'Declaration of Conformity' and just stole a document from the internet at random, didn't you?" They apparently didn't even look at what the standard was lol.
There's also a lot of products that end up in circulation with "UL" or "CE" marks on them that are fraudulent, usually from one particular country that has had a tendancy to say "oh, that's not the European "CE" mark, that's "China Export". That's another whole topic and I've written a book here that I'm betting very few will read lol.