[watwut]

That is something you have to do when you do speculative trades. That has zero to do with managing inventory.

You are not required to take loan to buy futures. You can do so, because then you can bet more then you have. But you dont have to.

[seanhunter]

You have to have a margin agreement in place to do any futures trading regardless of investment/hedging/speculation purpose. It's a requirement of the futures exchanges. For example, here's the "about margin" page of the CME group

https://www.cmegroup.com/education/courses/introduction-to-f... what-is-needed.html

"Futures margin is the amount of money that you must deposit and keep on hand with your broker when you open a futures position. It is not a down payment and you do not own the underlying commodity."

Notice you have to have margin on deposit to open any futures position.