Proof of age is not required for this stuff.  Article 2257 compliance is not necessary unless there is actual or implied sexual contact.  A naked 17 year old coming out of the ocean is not illegal to photograph.
I am not saying I agree with this or that I would shoot it, but it is legal.
Think about the drunk slut shit you see during Mardi Gras. The models may be getting paid, but what about the other people in the background?  Do you think they have a release on file? Check out the "Girls Gone Wild" stuff.
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