Worse, I have used services where they changed the email validation code years after setting up my account and then I could no longer log in because my email ad

Worse, I have used services where they changed the email validation code years after setting up my account and then I could no longer log in because my email address had a + in it. So I don't do this anymore. Sneakemail, which lets you do it with hyphens, works pretty well, though.