Once you open them you have to consume them.

A short conversation with M:

me: honey, where's that other bread stick we bought the other day - you know, the one you cook in the oven?

m: it's gone.

me: what, you mean the other one too?

m: yes.

me: you ate all of it? all yourself?

m: yes, gone in this end [points at mouth] and out the other end [makes pooping noise]

me: oh, okay then.

m: once you've opened them you have to consume them. it says so on the packet.

me: oh.