This is true, but in the Skyrim case nearly all items are small enough that a 'near optimal' answer is the indicated algorithm, with that extra space a more lit

This is true, but in the Skyrim case nearly all items are small enough that a 'near optimal' answer is the indicated algorithm, with that extra space a more literal 'garbage collection' free zone. In videogames, making the user GC isn't fun, and therefore reducing the number of GCs is more optimal than strictly solving the problem.