There have been countless stories about "fakery" during the Olympics opening ceremony in Beijing. From the piano not being real and the singer being substituted, to some of the fireworks being CGI and the ethnic kids not being truly ethnic.
The opening of the Olympics games is a show, just like any other show. It's on a much grander scale perhaps, but it is a show none the less.
Shows are live. Things that are live have a knack of going wrong. Much of the production time of a show is put in to reducing the risk of things going wrong. That is why most shows have a prompter; It's why there are understudies; It's why we have rehearsals.
Shows are also fake. Nothing is real. Nothing! Anyone with a vague knowledge of putting on shows knows this. The acting is fake: The actress playing Juliet doesn't really kill herself (even method actors draw the line somewhere). The scenery is fake: That's not a real bus in Summer Holiday. Even the flying car in Chitty isn't really a car. It's a life-size model on wires. (Sorry to anyone who thought it was real).
And that mottled lighting effect in the woods in Babes in the wood? The stage crew open the roof and allow the sunlight to filter through the 5 large trees they have planted specially amongst the tabs. They really do. Honest! ;-)
As humans we have the amazing ability to suspend our disbelief even when given very little information, particularly with other humans. This ability is used all the time by directors/set builders/lighting crews/make up artists ...
Of course the piano was fake. It had to sit on a piece of flexible flooring because the flooring was lit from underneath to make the scroll work without any shadows from the people moving on top of it.
Of course some of the fireworks were CGI. They had to make sure they looked right when they were live in front of a massive audience. Also, the fireworks were set up but they felt it was unsafe to film them (see the paragraph at the bottom).
As long as the games are real I don't mind fakes at the opening ceremony.