@RCHEW, the cost to use a Roku device can easily be $0; there is no mandatory fee. There's plenty of free "channels" out there, but don't expect to receive cable channels or even over the air channels without paying and of course things like Netflix, Paramount, Peacock, etc. are going to cost money.
If you're not going to subscribe to anything through Roku there's no need to add a payment method to your Roku account, although they don't exactly make that obvious.
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