SnowWolf said:
Check out this girl who got her art stolen by Old Navy

That sucks. I don't know anything about the status of this case but I would be very surprised if any judge would decide in favour of the company. It looks like a "watertight" case. Same with the theater poster case.
But I can't deny that there are issues here and that watermarks are a way of fighting that.
In the same spirit:

mabit said:
another one where the guy just straight up posted a pic of mine behind his patreon paywall

I would assume that Patreon immediately suspended this person's account and withheld the money.
My point is: There should be other means to fight that. Whether those means are sufficient I don't know, though.

mabit said:
Instead of saying that "Artists are a weird breed" how about trying to have a little more empathy with your fellow human beings?

I did not mean to offend you and I am sorry if I did. My sense of humor is... let's say "not for everyone".
It was just a bit of banter.

savageorange said:
Fourier watermarking

How well does this algorithm cope with JPEG compression? I would assume that re-compressing an image would mess up the outcome of the fourier transform. Or the artefacts introduced by the watermark would have to be much more noticable than the artefacts introduced by the JPEG compression.

Munkelzahn said:
But I'd suggest two things
a) add some background (preferably also rendered, not a photo)
b) add a wolfcock/wolfdildo, standing upright and "penetrating" your character
this will greatly improve your chances of approval

I did some things: https://puu.sh/AX02j.png
I gave Donut Steel a buddy: Jimmy (Get it? He has jimmies on top.)
a) I don't have any good backgrounds aside from the stock photos in SolidWorks. And I don't want to model one because it would look bad. So I chose to have an abstract background.
b) I saw a wooden stand like this for holding pretzels. The german word for stand is "Ständer", which is also an euphemism for "erection". The material is oak. The german name for oak is "Eiche", which is sometimes (maybe intentionally) misspelled as "Eichel", which is a name for the "glans". I don't think I can fit more innuendos for penetration in there. They're even blushing.
I spent way too much time on this :D