Come out with a credit card that has a debt limit of zero, that is you can't actually charge anything to it, but it is in every other way valid.

This way when you have these sites with opt-out free trials, that is free trials that at the end you have to go in and opt out, often made so complicated as to be easier to cancel the card, rather than having the service just terminate if you don't opt-in at this point, you can use this card for the payment info, enjoy your trial, and then the billing will fail so you automatically opt-out on these opt-in bogus sites like youtube-tv.