Just use a single vendor credit card. I do this all the time with Final (getfinal.com).

>Why would I trust that some online coffee merchant I've never heard of isn't up to the same tricks?

Because they use "recurringcheckout.com" as a payment processor, which lets you do this.

This is enough of a hassle that I will never make the purchase, despite being interested.

I would also not sign up for a subscription service that does not let me cancel without contacting customer service. It's a dark pattern that too many subscription services adopt. The only reason for this is to make it more difficult to cancel. I was about to visit your site and try it out (depending on price), then I read that comment. If your willing to make it hard for me to cancel to try and squeeze in an extra buck then what else are you willing to do. I feel like it's shady and makes me not trust your company.