You might be at work (away with car) while the midday sun is filling your home battery.
In my case, I live on a very shaded property; no solar for me. I also live next to an electrical substation, so extended outages from storms is highly unlikely; I'm first on the fixed list every time. In my case, the home battery doesn't make sense, but the EV might still.
EVs as grid storage is an option that may be compelling in some areas and for some people. I think that's worth exploring.