Thanks for that; I had ignored the Adobe leak, because why would I have created an Adobe account? Turns out I did at some point, so I guess I'm the goat there.
Often you need to create an account or somehow register your email at sites, just to get something very basic, like a free download, or use a feedback form.
I entered my address out of curiosity and it told me I had an Adobe account. I can't remember ever creating one so I tried the password reset process. Adobe tells me there doesn't exist an account under that address.
How is this possible? How did Adobe leak my address if I don't even have an account?