Major shortcoming of iTunes Match is that it (seems to) only work for songs purchased through iTunes - and the entire playlist containing songs purchased via other providers will not synch over to your iCloud devices. Watch a sham!
So.. songs I've purchased through amazon or even CD are left out of the cloud.
BTW. The iTunes display of the iPhone synch simply states that iTunes Match is turned on... but doesn't give any instruction as to how to turn it off... just how to turn off iTunes Match for iTunes (which is different).
Here's how I solved my own problem:
1. Disconnect iPhone from iTunes.
2. iPhone settings Music>iTUnes Match = Off
3. Connect iTunes > iPhone > Now it's possible to synch playlists for ALL of your music in iTunes.. not just the iCloud approved songs.