The issue is that the catalog has an error in it.

AR-10 top ends that were supposed to ship without carriers and charging handles were pictured and shipped with them.  We've got some orders on the books, and they'll ship with the extra parts.  New orders will be corrected.

These parts are more expensive than M15 parts, and many customers prefer to use the carrier and charging handle from their existing rifle in them.

We'll double check the 15 parts too, but currently the problem is only with the 10s.

Sorry about the confusion.