Also allows him to carry additional people and items, and store the items. However, might be better to have an SUV or similar for greater and more secure storage.
Now I need a comic where a Flash uses the speed force to carry the entire Justice League Watchtower into another dimension and it just follows the characters who now have to live with the fact that they failed in their original universe. Green Lantern retires because the hope is gone, Aquaman works out a schedule with the new universe Aquaman so they can split the responsibilities of head of Atlantis and superhero work, etc.
Most media just has superheroes consume regular calories for their body size it seems. Where does all this extra energy come from? Guess Flash has the speed force, Hulk the gamma radiation, and Superman the star power. Only two I remember someone eating extra calories is Pecorine from Princess Connect and that one girl who can create anything from My Hero Academia.
Could he learn to vibrate his genitals so fast, that they become a blur? That way he could walk around butt naked but no one would be able to see anything except a blur down there.
Writer Cary Bates says that the Supermobile was created as a promotional tie-in for the Corgi Toys toy line: "In my opinion, whenever merchandising needs are dictating story content, the odds of any real creativity or inspiration are severely compromised".
I don’t think it’s a waste - we know he can bring things with him when uses the Speed Force (his clothes), so being able to travel without needing to run and use up stamina isn’t the worst decision.