Costa Reefton Sunglasses

Why in the details does it talk about Olaf and the movie Frozen?

Is glass really worth the extra $ ?? i've never owned glass sunglasses but i am debating the purchase here. used for fishing in oklahoma

From what i have read on coasta sites the real coastas will have 580p engraved in small print in the corner of the lenses , do these have the engravi?

I do not see anywhere in the product description if these are glass or plastic lens, and if they are 400G, 580G, or 580P?