The hack I use for subscriptions is to pay with a money order, mailed to their location. This makes it impossible for them to autorenew. I started doing this after discovering to my dismay that one subscription used my checking account routing number to auto debit a subscription renewal the following year, at a significantly increased rate, direct from my checking account! I don't see how this isn't larceny or bank robbery.

I also track who is selling my name to marketers by using initials. So my subscriber name instead of Bob Jones is Ned Y. Jones for the NYT sub, Will S. Jones for the WSJ sub, and Roger D. Jones for the Readers Digest. Then when I get mailed an ad for sex toys advertised to Ned Jones, I know the NYT sold my name to them.

They offer a discount, you just say no. It's a nuisance, but I wouldn't reconsider a subscription to what is maybe the best newspaper in the world because of it.

Citi credit cards (and maybe others) have a good feature where you can set a "virtual card number" with a specific credit limit and/or expiration date. Great way to ensure that your card can be charged once, then payment is denied when a company tries to auto-renew you.

I've heard that if you use privacy.com with a California mailing address they let you cancel online due to California law.