Additionally, I just got an email with a support chat transcript and as part of the chat he's been asked to confirm his details including his email address... He's entered my email address! He's actually entered it twice during the chat, so it can't be a typo.
Now I'm wondering how he can possibly think that's his email address if he hasn't actually logged into it?
Honestly, some people are just dumb/careless and will make the same error repeatedly even after you've contacted them to let them know.
One guy was even adamant he'd got my-email address (I'd been CC'd along with some other business address belonging to him) and was kicking off - gmail dot issue confused it too... what had actually happened is he'd registered a firstnamelastname address and made a typo somehow missing off the first letter...
so his took the format "owielastname@gmail" vs my "dowie.lastname@gmail" and he was angry that I was "getting e-mails without the dot".