Good point. I assume that there is now no way to "shuffle all songs" on a device with iTunes matched on if your library exceeds your device capacity assuming you cycle through all songs (whch is doubtful). Still, it's pretty irritating that in order to then get rid of all songs downloaded with the shuffle, you have to remember what was shuffled through that was not on your device.
There are so many negatively to iTunes Match right now that you have to be insane to turn this on at a device level. For me, it's worth the $25 for simply get upgraded version of songs that it can match and to have backup for my entire library, including metadata. Once I go through that the first time, Im turning it off on my PC and NEVER turning it on my device, at least until the 10 or so major flaws with this whole process get worked out.
Tony