Lisa from "The Whole Cake & Caboodle was kind enough to create a tutorial for you all, on how to make the sacks. She suggested they would be good sandbags for Army parties, amongst other things.
Step 1: Roll out white, grey or light brown fondant until around 1/2 - 1 cm thick or as desired and cut into rectangles approx 3 cm by 5 cm.
Step 2: Squeeze all edges of each rectangle to get a result like a pillow shape. These dont have to be perfect as they are a sandbag and it adds to the character.
Step 3: Use a seive and push the pattern into one side of each sandbag. It doesn't have to cover the whole bag or be perfect and any bumps are fine.
Step 4: Score a line/seam along each edge although this isn't necessary and it doesn't have to be perfectly straight as it gives the illusion of full sandbags.
Step 5: Lustre in spots or use petal dusts as required to give the finish/colours wanted or leave plain if desired.
For my overseas readers Pipi's are a shellfish (from Wikipedia the free encyclopedia)
Paphies australis, or pipi in the Māori language, is a bivalve mollusc of the family Mesodesmatidae, endemic to New Zealand.
The pipi is a shellfish with a solid white, elongated shell with the apex at the middle. It is covered by a thin yellow periostracum. It is abundant in sandy and silty mud in estuaries, and harbours where there is considerable water flow. The daily limit is 150 per person, and although a minimum size is not stipulated in the regulations, only larger pipi should be taken. For Māori, pipi are a traditional resource. In earlier times Māori made specific flax baskets to gather them. Smaller specimens would fall between the woven strips and back into the beds as the basket was gently swirled through the water.
Maximum length is 83 mm, and height 51 mm.