KLM are now allowing economy passengers on most international flights from AMS the opportunity to "upgrade" their meals for between €12 and €15. Standard meals are still available. So the arguments about logistics is being tested in a far bigger cabin than Club.
Only on one of my CW flights I was told my first choice wasn't available - but then she delivered it anyway! And on only one of my Y flights, across all airlines I missed out my first choice and had to have the Vege option. As long as it isn't a fish or game option, I'm happy.
While the whole "book the cook" scheme sounds nice etc, I wonder how much of it is marketing spin for the airlines concerned. A game of one upmanship. Without knowing the mix of people that actually have a choice when they're flying compared to those that have to fly an airline because of route/company policy etc it would be hard to see the effect of this. It's like saying Ryanair has the cheapest flights, which is a useless statement for me as Ryanair don't fly anywhere I want to go to (or airport if we want to be really pedantic!).