Chromebooks do not require an internet connection. Even when they do, how many users need cellular data?
The thing about $250 laptops is that Chromebooks at that price are not shit at all. Think of the things you can't do on a Chromebook. RAW photo editing, video editing and advanced Office features are the main ones people mention. Now imagine doing those things on a $250 Windows laptop! And how many people where you work need video editing and anything which can't be done in Google Docs or the native Office editor?
Chromebooks do 99% of the stuff average home users need to do. If they want to get a new Windows PC which does that 99% as fast and smoothly as a Chromebook, they would have to spend many hundreds. But they would not have a rock solid OS and inherent virus protection (in Chrome OS everything is sandboxed and it verifies the OS every time it boots). So for the average user suffering Windows slowdown the best option is to get a $200 Chromebook for 99% of their tasks and keep their sluggish Windows PC to boot once in a blue moon for the other stuff. How would the market look if people did that?