The reality of cheap solar panels is that batteries are now the more expensive part of an off grid system. And for a grid-tie system the permits, inspection, and professional installation is a big burden in the US. All those regulations are annoying, but when you’re playing with thousands of watts it’s reasonable to ensure the safety of linesmen, firemen, and occupants.
Grid-tie ends up being cheaper than battery systems and maximizes solar production of the panels as power doesn’t go unused when there is no load and the batteries are full (or near full, as they can’t charge as fast then). You’re basically using the grid as a big battery; give it energy when you produce it but don’t need it and get it back when you actually need it. That won’t scale up forever, as the grid isn’t actually a battery (yet anyway).
I’m thinking about an electric car and a grid tie roof system. I’d rarely be using the actual electrons my roof generated in my car, but it’s nearly as good to say my house generated more power than my car used.