The council have clearly missed the point in their statement. It doesn't matter how much choice is available to the children if they don't know about it. And the blog clearly shows (not in a nasty, troublemaking way) that the kids don't really understand what's available to them for lunch. That's something they should be addressing.
For example, Martha was told she could have unlimited fruit, salad and bread but none of the other kids were. So she told them. A few posts later the school officially told everyone. But still poor Martha seemed confused about when she was allowed fruit and salad and when she wasn't. This wasn't Martha's fault; the school need to make sure the kids understand what they're allowed so they can make choices.
Argyll and Bute council has managed to make itself appear to be a shambles really. Go them! They could have responded in a sensible manner to perfectly reasonable criticism (like kids feeling hungry after a teeny tiny portion of lunch, or not getting a balanced dinner), but they chose to act like nincompoops.