"As much of a sacrifice as people say this is for me or Oprah or the president to come for these few days," the first lady told a group of fellow Chicago 2016 boosters, "so many of you in this room have been working for years to bring this bid home."
I would say that the sacrifice was to the American people who had to watch their tax money "fly" away. I just read somewhere that out of 80 some sentences the Obama's spoke for the Olmpics there were approximately 70 references to themselves. (I/me/myself/etc)
I'm sure glad that these people are representing the American people. 
If the rest of the world thought that the American people were all about themselves they sure have proof of that now.