Yes lyndal, sometimes the satchels can arrive with holes in them.

The satchels are perforated... they ALL have holes in them.

Plus the seal at the "open" end is not in any way waterproof after you fold and stick it down.

Ziplock bags are the perfect cheap way to deal with waterproofing. Not freezer bags, the normal ziplock bags - I get mine from Aldi and Coles (Hercules brand)