The landscaper in me wants BUCKETS of those 6 x 5 plant leaves.
I crammed one hundred of the 6×5 leaves into a PaB cup. That makes them about 17 cents each, including tax. Also, there were lots of little spaces in the cup which could be filled by 1×1 plates. This does not take into consideration discounts for bringing your own cup or VIP points. However this purchase would be contingent upon a LEGO store having the 6×5 leaves in stock.
Conversely, right now, if you wanted a quantity of 100 of these leaves, you would pay about 34 cents each, including shipping on bricklink. Incidentally, this part is not currently available on the S@H website.