im really not sure why this topic has been popping up so much lately. there are many, many reasons a "frag" may cost $1000...too many to list here, but some of them are: rarity, perceived value, depth of collection, point of collection, transport, etc.
why does anybody spend their $$ on anything? because they want it and can, simple as that. Your house payment is another guys night out or dinner date! its all in perspective.
this is a hobby, which is a way to spend your excess time/$$. Some of us have more time, some have more $$, and some have more of both. Some people, think any aquarium/tank is a waste of money and cant imagine how you spent $100 on that coral.
To each their own...if you dont like it or want it, dont buy it. Really is that simple.