Is it acceptable for a Political leader to shun the National Anthem?

[Samus Aran]

I'd wipe my ass with my country's flag if I ran out of toilet paper.

If I ever won the Tour de France I would bribe who ever responsible to play a Xenoblade Chronicles song at the podium ceremony instead of my national anthem.

Oh and this is funny, look at his face:

Then, 2 years later, this happened to the same cyclist:

Here's the Belgian Prime Minister who mistakingly sang the French National Anthem instead of the Belgian one. LOL, just the thing to do in a country where the language conflict between the Dutch and French is the biggest issue.