Because that increases the cost exponentially. As soon as you do grid connected with sellback there is a huge amount of red tape and the power company has to be involved then Blueprints and only approved installers can do the work.

Offgrid self consumption you can just do yourself. I spent roughly $20,000 on my stuff. But that got me a full pallet of 30 panels, 30 kWh of battery, 16,000 watts of inverter output.

For $20,000 most solar installers won't even talk to you, at best they'll give you like a small handful of panels and an inverter with no batteries. For a setup similar to mine you'd be looking at like minimum of $90,000 for grid tied from an installer. It just doesn't make financial sense.

It's honestly criminal the upcharge that solar installers take. It's not even difficult work the NEC is freely available to all and while it is a lot of reading it's less than a Harry Potter novel I was able to get through it all get my installation done and then had a master electrician come out and inspect it. Passed, it's just about making sure you use the correct gauge of wire, make sure everything is spaced how it should be, make sure you have Breakers and disconnects in the correct places. Definitely not worthy of the ridiculous amount of money solar installers are charging