Because none of the OTC securities are traded with human intervention at all, in fact clearing and settlement is also strictly computer driven (DTC Eligible Securities). None of this anymore requires a human being to be involved removing the human element and making money on volume of trades per day and taking advantage of "market orders" when they occur for internalization (spread).
To suggest they buy and sell for their own trading strategy means they invest and speculate. Nevermind the risk involved but also the costs alone for having a position on deposit costing them 20% of the total trade value. It makes absolutely no financial sense to trade OTC securities based on the cost aspect. But as it has been pointed out the illiquid environment and ridiculous volitility here makes it impossible to do so. Oh did I mention the other cost if volume were to exceed NSCC guidelines for an illiquid security? Exceed that 20 day MA for volume and well stand by for additional fees. There is no profit margin here for trading, combine that with the risk and forget about it.
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