Do you have "catch all" turned on via your email?
Any email that's sent to my domain will be redirected to one of my mailbox's
e.g.
[email protected]
[email protected]
will be redirected to my true mailbox:
[email protected]
So they only have to misspell the domain, rather than the whole email. I get an email a month that is not intended for me (but is a genuine email for someone)