It reduces weight i guess.
If it’s only a couple of decorations, I doubt it does

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I just Googled for proposed carbon fiber airliner seat designs, and found
these monsters. They promise to reduce 2360 kg per one
A321 (as I know, that amount of extra fuel should add almost one hour of flight for this type), but it’s unlikely for them to be certified — just the non-foldable armrests are enough to react with JJ Jameson’s laugh

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