My gmail is a word (a profession - can you guess which one?) that for some reason people often decide woild make a good fake email to give out. I get a lot of spam to that account, most of which i ignore, but when I get on certain mailing lists (conservative or religious) I give them one chance to remove me before I start trolling. I’ve also had people sign up for many services using my email (some of them even paid services, or in one case, a federal student loan account) so I get the “confirm this email” message a lot. I ignore it, but if the service contacts me again, I usually do a password reset to make sure the account isn’t accessible by whoever used my email.
Almost all of these incidents are intentional misuses of my email, but on occasion I’ve run in to someone who used my email by mistake - usually because they have the same address but with a different domain (i.e. hotmail, yahoo) or they have added a number to the word and forgotten to include it when signing up for something or filling out a form. When this happens I will contact the person if I can and let them know that they’ve used my email accidentally, and caution them about making sure it doesn’t happen again. I’ve met a very nice (and apologetic) meteorologist from somewhere in California, and a really mean real estate agent from Nevada because of these errors. The real estate agent currently has a subscription to MLS that she can’t access because apparently her parents didn’t raise her to be nice to others.