Change.org - from your response: "When people sign a petition, they receive a confirmation email that gives them the opportunity to remove their signature if they didn’t actually sign it."
That is not true. I have signed many petitions and have yet to see that in an email. In fact, what I do see is a prompt for me to share it. I just double checked my inbox for one I signed this week and nope, that is NOT in the e-mail. At all.