Yep, I live with this too... I thought it luck that I got @gmail.com early on, turns out it was a curse. It's not a _common_ last name, but people with the last name seem to assume it is theirs, or maybe people miss the other letters in addresses they are given and just use the last name?
I used to get periodic emails from an elderly German couple giving me their train itinerary for their upcoming visit. I politely reply that I'm not their cousin, and consequently their cousin probably won't be there at the train station when they arrive. And then six months later it all starts again.
I have what I assume is a distant cousin on the east coast and I get an email with an invoice every time the pest control folks come out to his house to spray. No option to unsubscribe, and I've given up calling the company to let them know they have the wrong address.
There is a fellow in Quebec whose == , and for a while I got monthly emails because someone was trying to wire him money. Again, no option to unsubscribe.
Lately I've started getting emails from universities interested in admitting another distant cousin in Oregon. I'm guessing some college lead-generation service crossed her name with my email (her/our last name). I haven't figured how to handle that one yet, I'm contemplating printing a few out and (snail) mailing them along with a note.
But I've had the address long enough that I don't want to let it go, so I guess this is all a necessary burden......