It’s the same mentality that results in someone killing a zoo rhino for it’s horn.
It’s not the functionality or use they are after, it’s the idea.
Ornaments. Like many “luxury” materials, the value of ivory is in its scarcity, not in any of its physical attributes or its appearance, for which substitutes exist.
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It’s the same mentality that results in someone killing a zoo rhino for it’s horn.
It’s not the functionality or use they are after, it’s the idea.
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I guess i will never understand People 
Yes, there are substitutes. But they are widely considered inferior both in physical properties and appearance. A substitute that was truly hard to distinguish from real ivory would be of enormous interest.
IOW, its high value is due both to scarcity and its properties.
I seem to remember piano keys were made from ivory. I imagine the substitutes are perfectly adequate, and that using ivory made no difference to the sound, because why would it ? The sound doesn’t come from the keys.
And it was a poor reason to kill an animal anyway.