Consider it a suggestion to developers who are tempted to implement cool new tech on a site just to tickle their own itch.
> The Pentium III processor's Internet Streaming SIMD Extensions Instruction Set has been a hit with software developers resulting in numerous optimized Web sites and software applications available today.
[0]: https://www.intel.com/pressroom/archive/releases/1999/dp0517...
And you're ignoring huge benefits like offline availability, push notifications, storage...
Good news is that a service worker can't do that. It gets automatically shut down after a short period of time. It will be woken up again in response to push notifications, which you must request permission for, or in response to a new user event.
> Maybe my users pay for their data, or maybe they have a poor connection.
Which is why providing greater offline capability is a good thing, not a bad thing.