That's entirely due to the US scheme, where utilities have ensured that it won't make sense nearly everywhere. Which is then combined with the asinine permitting situation in the US, where every city and county does something on their own without any order or sense.

This combines to ensure that any solar installer will do lots of very expensive things: 1) have a large sales force to close the sale, which last I looked accounted for 30%-40% of the overall cost of solar in the US, 2) roll out trucks many different times during the planning and install, each costing lots of money, 3) never have to compete with a bunch of other hyper-competitive installers and find efficiencies like batching installs together in the same general area.

There are also massively high solar PV tariffs in the US, more than tripling the cost of the panels, but that's not even that big compared to the rest of the needless inefficiency in the system.