I'm kinda surprised people aren't just buying a 3D printer. I print stuff all the time. I'm not into this kind of game but if I were I wouldn't pay that much for a piece of plastic I can print at home for 3 bucks.
Note that a standard printer won't be anywhere near as nice quality as official models. You need a resin printer for that, which requires ventilation, some basic PPE, and additional labor to clean and cure the prints correctly. Not something you want to do with small children or pets in the house.
We resin print most of our models. We use FDM for blocky things like tanks and buildings, though. And some complex or very large models can't be printed (although we sometimes use alternatives for those).
Warhammer is an unusually expensive game, too. Other games like One Page Rules will sell you STLs to self-print, or charge very reasonable prices for pro-printed minis. You can buy a 2-player starter kit for OPR for about the same money as one WH40K unit.
But cool to hear you're printing them. I can imagine they don't want to allow it at official tournament to protect the golden goose :)
Of course it's not the resolution of a good laser resin printer but resin is also much more expensive and it's a PITA to work with as discussed here.
The extra cost of resin is negligible at this scale, it's mostly the safety requirements and extra labor that makes it harder.
We need a resin printer tuned for mass production of tiny pieces, just like belt FDM printers are tuned for mass production.
FDM prints are either slow or have obvious layer lines or both. If you're painting it maybe that doesn't matter.
I have several printers and I ususually have something "in the oven" while I WFH (my job is not related to 3D printing sadly)
The limitation with injection molding is typically the cost and complexity of having mold plates made when you don't have a demand for all that many units.
It's fine as a token for the game, but people enjoy the painting etc too.
A resin printer isn't safe for use in an apartment, otherwise that would probably be more common.
That rules out most apartments in countries like the USA and UK.
* Do not locate dedicated work/personal spaces in close proximity to the printers if odors are a concern
That rules out all small apartments, where there isn't a room that can be dedicated to the printer.
* 3D Printers and uncured, open resin vats should be stored and operated in a well ventilated area or with local exhaust
That rules out all apartments in northern countries (like here in Denmark) with lots of insulation
And if you actively went it outside carpet and close proximity should ok ok'ish health wise. It's just effort and noise that a lot of people don't like to put in.
Yes I've always wondered why they love carpets so much. When I lived in such an apartment it was terrible. Always dirty and dusty. I'd much rather have a plastic, wooden or tile floor (the latter not ideal due to breakage though).
But you can ventilate, especially if you blow the air outside through an active blower.
And finally, makerspaces are a great way to do these things anyway. A community that can support and help you when you run into issues, friendly people around to borrow equiment and materials from, and they're usually pretty cheap if you don't get a fixed desks.
It's no more dangerous than a craft like woodworking or spray painting when you follow very basic safety protocols, but the safety culture is near nonexistent in the community.
Not everyone is as careful with the stuff so that doesn't really help.