There are a number of industries that also do this where they'll be voluntarily shut off or pulled back during times where the grid nears brownout/blackout beca

There are a number of industries that also do this where they'll be voluntarily shut off or pulled back during times where the grid nears brownout/blackout because their processes are interruptible with minimal cost which for battery charging stations is pretty true unless they're entire stock is at a very low charge.