There is no free enterprise where speculation is considered illegal.
Speculation creates no product, no asset, no good for society.
When people pay the price that speculation adds to goods, they receive nothing for it. They must work to earn the money, yet receive nothing for that money. Working without receiving anything in return is usually referred to as slavery. It seems odd indeed to equate slavery with freedom. Paying for the added costs of speculation closely resembles paying bribes, extortion, blackmail, or protection money.