You still have ethics ground if you think it the same way as repairability, actively blocking ways to repairs things you bought yourself is questionable, and keeping things closed source can be seen as a way to artificially prolonge a strict dependance on your vendor by impairing your ability to resolve issues by yourself.
No, for most it's because they evaluated a number of ethical, social, and technical concerns, and think so.
It's probably illegal too, as in many jurisdiction the public, or at least a health/food regulatory body should know the process and ingredients.
Take into account allergens, and on top of a matter of public knowledge and health, it can also be a matter of life and death.
If you actually care about this, stop alienating potential allies, and ideally start making arguments to support your case instead of telling people to RTFM (which in this case is even worse because "the manual" isn't as much of an authoritative mic drop as you seem to think it is).
> We campaign for these freedoms because everyone deserves them. With these freedoms, the users (both individually and collectively) control the program and what it does for them. When users don't control the program, we call it a “nonfree” or “proprietary” program. The nonfree program controls the users, and the developer controls the program; this makes the program an instrument of unjust power.
It seems safe to say the author thinks that one creating "an instrument of unjust power" for oneself is unethical. Though, perhaps if the commenter in question pulled that quote out of the article, it could have helped their point.
