Earlier quoted context omitted.
I'm Irish and have a common firstname.lastname@gmail.com At some point the head of a national hospital thought he had that address and wasn't using his official email for everything, I got several emails that should not have been for me and some were quiet sensitive, I always emailed back the sender to let them know and eventually I emailed his secretary as it kept happening. I've also received purchase order confirm…
My spouse suffers from this as well. It's bananas to me how many people use that email address clearly thinking it's theirs.
Neither of our names can be confused with a last name and yet I had multiple people writing to it incorrectly, including: as the email attached to a Diners credit card (I called Diners and they asked me what's the right one and "if I don't know the right one how do I know that it's wrong"), as the email for a school 400 km from home (another family must have had the same idea), once for some lawyer stuff (I then learnt that about 100 people in Italy do have my wife's name as a very uncommon last name), and lately as the recovery email for another Google account.