As with most things you sign up for, the signing up is a lot easier than cancelling. Wanting to switch back from 'paperless', the bank says the website is a separate entity and has to do it, and there's no place on the website to 'un-sign up', or a website number to call. Sort of like the phone company, and the cable company...

What I've done is gotten a credit card that is used for online stuff only. Easier to keep an eye on, and, if it needs to be cancelled, it doesn't leave me with no card to use in RL. I would suppose you could get a pre-paid credit card (available just about everywhere), load it with just what you need, and either pitch it when empty, or keep it loaded with a very small amount.