How is this not more wasteful than running a native app? You have to run a Web server IN ADDITION to the app. And your client-side is rendered in the browser which, again, is IN ADDITION to the app. Where the native app is just... the app.
Sure, many people seem to be running their Web apps on the local Web servers because Web development is all they know, I'm just pointing out how it's less efficient that native apps.
I'm sorry, but that just isn't how that works. It would be no more "wasteful" than running a native app. 1 user or 10, it doesn't matter.
Besides, most self-hosters have servers that are running many apps, so this is just one more. Not a big deal.