The more batteries available for that arbitrage, the less effective it is. As a grid user, I'd rather the grid own and operate those batteries. Certainly some of my outages are due to line issues between me and the substation, but I think more of them are due to line issues between the substation and its upstream. Having storage at the substation could potentially help all the customers and centralize the maintenance and safety burdens. They could do some energy cost arbitrage (although I live in the PNW and we generally don't have time of use cost distinctions, because hydro doesn't care)

I do have a 35 kWh propane fired generator onsite though, which does provide for outages regardless of where the break in the line is.