Generally OTC desks are useful for large purchases. Let's say you want to acquire $100 million in Bitcoin - you could go to Coinbase and just do it, but you'd drastically move the market, have a really obvious candlestick, and an observant third party could look for large movements from Coinbase and potentially track your holdings / de-anonymize you.

An OTC desk can be setup to spread the buy over several days / months, buy across markets, and optimize for best price execution. It's not necessarily a huge business, but a lot of businesses and high net worth individuals will use these types of services instead of trying to learn the skills themselves.

There are plenty of crypto exchanges that only deal with crypto. Or only have on/off ramps for some local currency that isn't really practical for people outside of that one country.

Bitprime allowed people in NZ to easily transfer value in and out of those exchanges. Or directly into a wallet for other services (i.e. buying NFTs or paying ransomware), or to hoddle.

The reasons for OTC desks is that if an individual wants to buy, say $100m of an asset, it's likely that they need to buy from multiple sellers.

If you do that by buying $10k x 10k transactions, your demand will increase the price of the asset and mean you pay more than current price for no good reason.

OTC desks either collect the $100m from large holders in big blocks, or they use working capital to constantly buy the asset and sell it for a single quoted price (hoping to gain on arbitrage).

In this particular case, they also offered the unique service of accepting /nzd vs. EUR/USD/JPY/KRW

Someone who doesn't want to keep funds on exchange but needs instant liquidity for any amount.

Also, the best OTCs tend to be failure tolerant: website down or DDoS'd? Doesn't matter, you talk on Signal or WhatsApp or Telegram.

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