There is considerably more care and overhead involved in collecting matchbooks with matches left in. I would suggest that it's not worth collecting a partial book unless the matchbook is an older scarce front-striker. Otherwise, carefully remove the staple and collect it as a matchcover.

I make an exception if it's a Lion feature match and hard to find. Then, the extra effort to collect it with partial matches is worth it for the extra beauty and eye appeal of a feature.