Can you be more specific about the app/channel you're using? The Roku isn't putting any of those ads in place during program breaks, that's being done by the provider of that channel. So, for The Roku Channel, yes it's Roku doing it. But any other app you're using has a different provider, and being on a Roku TV means nothing about the ads you see.
As far as The Roku Channel goes, since they provide all the content for free, ad placement is required to pay the costs of providing it. Putting up with ads is the price you pay for free content. That's why over the air TV has ads, and why so many providers on streaming boxes also have ads. Think of Pluto TV for an example. It's available on every sort of streaming player, as well as on Smart TVs (think LG Channels or Samsung IP TV channels). Even Prime Video and Netflix are starting to have ads on lower cost tiers, and you're paying for that content.
Dan
Roku Community Streaming Expert
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