It’s far less useful in the general case, but substantially cheaper and more efficient in a special case that consumes a substantial chunk of the primary energy used. It’s not as if battery storage is lossless. Currently, heat generation is often done using primary energy, but that too, needs to be reduced if we want to tackle CO2 production levels.

You can also use the same principle to store cold in summer: Cool down a vat of coolant (though water likely won’t do) at times when you have electricity surplus and use it later.

Certainly, that not solving all problems, but it can kill battery usage for some cases.