Depends, did you get a good deal on the filters?
If you paid full price, kind of pointless to have more than one or two extra.
If a good deal (like half off) or for multiple vehicles using the same filter, then yeah, I would stock up too (I have 5 Wix made Carquest Blue's for the Scion, they were ~$2.25 each).
And yes, they are stacked wrong, they should be in a 4x4 cube, not that weird lopsided tower with one facing the wrong way, and have the odd ball box in the back corner unseen, but first used.