Lord of the memes

Because the number you're reasoning about is the number of spears he wished for, not half the number he wished for, so mathematically, the logic holds for 3 different possible wished for integer values.

To arrive at precisely 12002 you need to make a further assumption which nobody has explained so far.

Also, a minor point, but that he wished for an integer number of spears is another assumption. Albeit a very reasonable seeming one, it's an assumption none the less. He could have wished for 12 thousand and π spears, for example. And no, I have no idea what you'd do with that ~14% of a spear.

If this were an SAT question, and upvotes correlated to what people were answering, well, the majority got this question wrong.