I think most people would be thrilled with the commercials blanked out...
Anyway, this sounds like you're watching these channels via a channel that is providing the stream independently of the original source, such as Pluto TV (I know, Pluto doesn't have these channels, but bear with me). When they rebroadcast the source, the are contractually required to not show the commercials. Why they do that I can't say. But I am certain it has something to do with licensing and the commercial contracts themselves.
It's completely out of your control. The only way I've seen absolutely everything being broadcast is with Locast and my local OTA stations. That's the only one I know that simply streams whatever is being broadcast.
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