Capacity and generation are two different things. Grid operators have capacity markets that ensure peak load can be met, and incude generations assets, demand response, energy efficiency, etc. Batteries absolutely coumt as capacity so long as they are managed to do so.
How can you possibly think the US military, or any sovereign country, will magically spend an extra $165B a year on meat a year if all of the current consumers magically go vegetarian? Who exactly is going to eat a bunch of extra meat? There will just be fewer meat sales, period, ignoring a short term price drop if everyone magically goes vegetarian on the same day.