Is this a a souvenir? I have seen things like this before, they were part of a soldier's "housewife" kit. Some of these kits were made to be presents from family member to a soldier. Rather than being a souvenir I feel this may have been part of a soldier's daily kit.
Recently, I picked up a bread bag (not WW1), tucked away in the corner of it was a small house wife kit. It must have been there for years with no one ever discovering it.