Are international friendlies necessary?

A few times each year, the managers for each country's national team will pick and choose players from different soccer clubs to participate in international friendlies.  The outcome of these friendlies have practically no importance since there is no championship to be won, and they do not affect a country's standing or ranking.  Often, the managers of the best soccer clubs in the world, such as Manchester United or FC Barcelona, hate international friendlies because many of their players receive a call up to play in the national team.  After the games, the players come back tired and can not play well in the league games.  On the other hand, the coaches of less important teams often benefit from international friendlies because not many of their players receive a call up, and thus, it becomes easier for them to defeat a team on a higher skill level.

Recently, Sir Alex Ferguson, the coach of Manchester United, gave a radio interview where he stated that, "I am all in favour of the competitions. The players should play in the major competitions; the European Championship, the World Cup."  Friendlies, however, are a different story.  He angrily branded these games as "a waste of time," when many of his key players were selected for England's game against Ghana.  Only a few days after his players come back, the team needs to prepare for a league game and an important game in the Champions League.  To him, it seems unnecessary to tire out his players when there is no feasible gain. 

Some suggest that national coaches should only be allowed to select a limited number of players from each soccer club to balance things out.  Others suggest getting rid of international friendlies altogether.  On the other hand, many citizens of each nation enjoy watching their national teams play.  Friendlies are another way to measure the progress of their national team.  What should people do??