@flagrant99, to answer some of your other questions, something through The Roku Channel and the stand-alone something aren't the same thing. They may or may not have identical content and if you subscribe through The Roku Channel that's usually, but not always, the only place you can view the content (not on the stand-alone channel/app or other non-Roku devices). As you've noticed, you can only cancel auto-renewal since all subscriptions are prepaid and nonrefundable. If you cancel it now you'll still have access until the end of its current term. It's up to you if you want to wait until the end of the current term to take out a direct subscription or do it now and have two active subscriptions or just stick with the current subscription. I can't speak to Showtime, but it's not unheard of for something to be available through the subscription on The Roku Channel that isn't available on the stand-alone channel/app, but it's usually the other way around (things available through the stand-alone channel aren't available through the subscription on The Roku Channel).
As you can see, there's exceptions and there's no one blanket answer that covers every subscription and every situation, but I agree with @andyross - you're always better skipping the 3rd party and subscribing directly on the provider's website.
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