They always are - at every Olympics, wherever it is held. It is the official language of the IOC, because the organisationwas founded by a Frenchman (Baron Pierre de Coubertin) and its HQ is in a French speaking city (Lausanne). They always use English as well - and the local language if that isn't French or English.
Stuart
You should read the history of the modern games.... see "Chariot's of Fire". The Olympics were re-born after centuries by the French. Their intent was to honor athletics.... sport for sports sake. To excel. Because it was done by the French, and the original Olympic committee was French, it has become the Official Language of the Games.
Soccerref
Both French and English are the official languages of the Olympics, see Rule 23 of the Olympic Charter.
We probably just stick it in French first because the French would whine if we didn't and it's best to humour them so they don't sulk about English replacing their language as the main international language.
It's the offical language of the International Olympic Comitee.
Pheem, without the French there would be no modern Olympic. Can we at least give them that much respect!
The Olympics are here in the UK. Why are all the announcements in French first?