Confirmshaming is the act of guilting the user into opting in to something. The option to decline is worded in such a way as to shame the user into compliance. The most common use is to get a user to sign up for a mailing list, and it is often found in exit intent modals and other popups. In the screenshot below,, Amazon uses confirmshaming to guilt users and discourage them from opting out.
Numerous examples can be seen at confirmshaming.tumblr.com.