foreign tongues from foreign tongues

I always thought that when the French spoke Spanish, they´d replace the [r] sound with a [R] or a [x]. (Look up the international phonetic alphabet and you´ll know what I´m talking about.) But according to the writers in Spain who made Harry Potter y las reliquias de muerte, the French replace every [r] with a [g], so Fleur always called Harry "Hagy." Weird.