They score more electricity by me not using it. Take the 30kWh a day that I generate and use my self and then multiply it by however many people there are with a solar, inverter and battery system and the relief on the grid could be huge.
And to add, most people with a decent species system have spare capacity in the afternoon after the batteries are charged and the washing machine and dishwasher have stopped. I could easily add another 10kWh to my total, but my batteries are full, my house doesn’t need it so if only I had someone to give it to