I realise that this is a marketing stunt, but potentially this could have a serious impact on the Boring Company. A flamethrower is a weapon, even if it's a 'toy' like Elon's flamethrower. This means the Boring Company is probably in violation of any open source license that prohibits use in evil applications - for example, the JSON license (http://www.json.org/license.html). I'm pretty sure that there's a bunch of other OSS licenses that prohibit their use in military applications too.
I don't seriously imagine for a second that anything will actually happen as a result of this. It's just fun to think about.
Interesting, though presumably as long as the flamethrower itself doesn't use the json library, they're clear. Though I now imagine a licence that blocks use by any company that manufactures or distribute weapons, for example. Or is in the coal industry. Is 'licence activism' a thing? Could it be?
It is a thing (most memorably a piece of software which is freeware normally, but you must make a donation if you air travel over a certain amount year), but it's rare. Most definitions of Open Source and Free Software do not include licenses with such restrictions (a core freedom being being able to do whatever you want with the software).
I don't seriously imagine for a second that anything will actually happen as a result of this. It's just fun to think about.