Or they could just have a similar gmail address they frequently get wrong (or that looks like yours when written in the terrible handwriting they fill in forms with)

There's probably a single digit number of people with my initial and surname in the world, and I still get order confirmations for one of them, car promotions for another and am on some sort of targeted B2B spam list for a third to my Gmail address in that format. I quite like the order confirmations tbf, most of them are for a fish and chip shop I actually used to get food at when I was a kid and my grandparents lived nearby so they're oddly nostalgic

Nah, this person just doesn't know what their own email address is and types yours instead (yours with googlemail). This happens all the time and it really isn't something Google can do anything about.