In a lecture updating the industry on FIFA's artificial turf programme, Fletcher said that the spread and acceptance of synthetic surfaces was improving with pitches now installed all over the world.
He said the international football federation were approving "football turf" (synthetic surfaces) where "climactic and other conditions make it impossible", particularly those countries where turf maintenance was too expensive.
He added: "In an ideal world, FIFA would prefer real grass but artificial turf is an alternative where conditions make it impossible. It is an alternative, not a substitute."
Though he emphasised the fact that synthetic pitches are not maintenance-free, adding: "Without maintenance budgets I would strongly suggest not to invest."
The football world remains deeply sceptical of synthetics, with fears of injury and its effect on the flow of the game chief among critics' concerns.
But most fears are unsubstantiated said Fletcher, with players accepting the surface once they had tried it.
He pointed to examples such as the World Cup qualifying match between England and Russia, prior to which, the media criticised the use of artificial turf.
But following the game not a single player or journalist called the pitch into question, acknowledging that it had been an acceptable surface.
The same situation had recently occurred following a German World Cup qualifier he said.
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