The C8 uses a different web services API than the C1, which included a notifications mechanism - effectively, when you made a change to the widget configuration on the server, it would post a message for the C8 to inform it of the change, and the C8 would poll the server frequently to see if it had any pending messages. That meant that the "reload" button was basically unnecessary.
However, when Chumby closed down, those of us trying to keep the systems up were in a mode where we needed to minimize the server-side costs to extend the lifetime of the system. The polling, while individually a lightweight cost to the system, was actually a significant portion of the bandwidth costs due to the sheer volume of calls for all of the C8 (and, at the time, dash) devices.
We had to throttle back the polling frequency from a minute or so, to hours, which is where it is now - in other words, it used to take the device well under a minute to detect a server change, now it takes hours. We felt this was a reasonable tradeoff because modifications of channels is actually a relatively rare event, but the we were eating a lot of costs by the design that treated them as frequent.
So - where we're at now is that at the moment, you have to reboot the device to detect channel modifications on the C8.