[mseebach]

No, I do think it is relevant.

If the purpose of the validation is simply validation, then what you call a false positive isn't actually false, as the e-mail address evidently was valid.

Including a very clear "I did not ask for this" link in the e-mail would allow false positives to undo any damage done.

Just because a technology can be used for bad (and this one is indeed - anyone auto-loading images in e-mail will be flooded with spam for that exact reason) it does not imply that any use of the technology is bad.