There is a time factor to markets too. I'd call it a market failure if someone wants to obtain a container and cannot do so at any price
for the indefinite future, but if you're willing to pay more but need to wait for an ocean voyage, that's just reality.
Markets are not magic - they don't let you ignore physical reality. They're just an eventually-consistent system that aligns incentives to meet demand. It's like a transcontinental trip: you can spend maybe $150 in gas and get there in a week, or you can spend $700 and get there in 6 hours - but (at least until Boom starts flying) you're not going to get there in less than 5-6 hours no matter how much you're willing to spend.