Until grid-scale batteries are more established, you're helping the electric company, and that's why they're exposing the arbitrage. They're providing the incentives to nudge demand, so a home battery is doing exactly what they want (use more at time X, use less at time Y). Otherwise they'd just have the 24/7 price be whatever it currently costs when the supply and demand curves are tightest for them (when demand is highest and/or supply is lowest).