checkMesh reports nonManifoldPoints on faceZones, which it shouldn't

Summary

checkMesh reports nonManifoldPoints on faceZones, which it shouldn't.

Steps to reproduce

Use:

pimpleFoam/LES/channel395

Run:

blockMesh

Just change the faceZones file to include some internal faces, see attached file:

faceZones

Then run:

checkMesh

Example case

pimpleFoam/LES/channel395

plus attached file

What is the current bug behaviour?

It gives error message:

Checking faceZone topology for multiply connected surfaces...
    FaceZone            Faces    Points   Surface topology                  
    someFaces           5        11       multiply connected (shared edge)  
  <<Writing 2 conflicting points to set nonManifoldPoints

What is the expected correct behavior?

It should not give an error message, since faces are always nonManifold (as far as I understand).

Relevant logs and/or images

See above

Environment information

OpenFOAM version : v2006
Operating system : Ubuntu
Hardware info :
Compiler : gcc