It's a perfectly valid question if one does the minimum to engage with the thing being showhn otherwise it's a reflexive and, as you can see in the several near-identical comments, repetitive trope.
Yes, but the difference isn't purely that this one is open source. It's also way cheaper (in terms of both money and also effort) to host because you can do as the demo does and use the free Google Apps Script for your backend and any of the free static web hosts for your frontend.