Presumably somebody is paying for the bandwidth and repository space for Fedora so you can get "free" updates and packages.
Who do you think that is, and why are they doing it? If it's the community, what are you doing as part of that community to support that system and help defray these costs?
None of these systems are free-as-in-beer - *somebody* is paying the freight. We're just a bit more explicit about how that happens - in our case, we make advertisers pay for it instead of our customers, our investors or the government.
You are correct that you bought a device, not a service. You are absolutely, 100% welcome to *not* use the service - we've documented everything you need to know to do whatever you wish with the device independent of Chumby Industries, and there's no EULA or other legal document that requires you to use the service in concert with your device.
Someone *could* conceivably create an alternative service to ours - however, in order to serve the same widgets, such a service would have to obtain permission from each of the widget authors to redistribute the widgets.
If, however, you choose to utilize our service and consume our bandwidth, we'd appreciate you using it in accordance with the terms under which we offer it - and please understand that we have the corresponding right to discontinue access to the same service to those that don't abide by those terms. As you pointed out, you didn't buy our service, so we have no obligation to provide it to you. The freedom you're advocating goes both ways.
Sound fair?