I've seen dozens of posts, on here and on reddit (not going to single any community out) questioning why anybody would pay for hundreds for what amounts to a "small piece of plastic."
But consider this, why is a hundred dollar bill worth anything? It certainly isn't worth the paper it's printed on, which amounts to fractions of a penny. However, the faith of governments backs currency, the expectation of all the users of the currency that they can easily exchange their denominated currency for an equal value of goods. Also rarity of the money. If the market floods with $100 bills, then each one is really worth nothing.
In this sense, I'd argue that ClickClacks are really a form of currency. I'd argue that the majority Clack transactions are done by trades. WTT threads are far more common than WTS threads. In this sense, Clacks merely function as the medium of exchange for goods, a form of currency in the community, with private sales periodically setting precedent for valuation. Different rarities of Clacks really just function as the various denominations, with clear and recognized price stratifications.
Liquidity in currencies is provided by the Federal Reserve, or a similar central bank; rules are made about the reserve rates, interest rates, and various other methods of control the bank has over the currency supply. The same is achieved in the here as mutual recognition of the future worth of Clacks keep liquidity high. In other words, it's very easy to sell or trade a Clack for either cash or for equivalent market value. Hardly any of the Clack WTT threads last for too long, and the ones on eBay always receive dozens of bids.
Even if you don't agree with this outlook. Then just view Clacks are part of the metagame. Do successful in trades and you might end up with something really nice from a seemingly nondescript piece of plastic. To question why Clacks, is to question why the entire skins/esport betting community exist. The keycap/skin merely serve as vehicles of exchange for value.
[TL;DR] When you give a $100 bill to a business, what are you really exchanging? What about vice versa, when you accept cash and give something away, why do you feel like that's a fair transaction? How much is a mere sheet of paper with some ink on it really worth? Instead of viewing Clacks as just a keyboard decoration, view them instead as a medium of exchange.
