[Izkata]

Based on a vague memory from years ago - so I could be totally wrong here - you're assuming knowledge he doesn't have.

Correct me if I'm wrong, but: The people doing the trading are middlemen, and have no capacity period. They expected to be able to sell it all off to the energy companies, even at a loss, so they normally don't accept any physical product. But the energy companies ran out of capacity - something the middlemen (traders) don't have direct knowledge of - so got caught unexpected with contracts they can't sell, and now have to accept the physical product.