Also why would you care if someone jerks off to a photo you uploaded, regardless of potential nude edits. They can also just imagine you naked.
Imagining and creating physical (even digial) material are different levels of how real and tangible it feels. Don't you think?
There is an active act of carefully editing those pictures involved. It's a misuse and against your intention when you posted such a picture of yourself. You are loosing control by that and become unwillingly part of the sexual act of someone else.
Sure, those, who feel violated by that, might also not like if people imagine things, but that's still a less "real" level.
For example:
Imagining to murder someone is one thing. Creating very explicit pictures about it and watching them regularly, or even printing them and hanging them on the walls of one's room, is another.
I don't want to equate murder fantasies with sexual ones. My point is to illustrate that it feels to me and obviously a lot of other people that there are significant differences between pure imagination and creating something tangible out of it.