I too was unaware that CC posts were not counted, but why count some forums, not count others, and debate still others?

What is the difference between these posts:

1) "Thanks" (in S.P.A.M.) = counted
2) "YHPM" (in CC) = not counted
3) "12345" (in OMNI) = counted but debated

Either count ALL posts in ALL forums or count NO posts in ANY forum!