> Profit is obtained by maximizing traded benefits and minimizing costs.

Gain is obtained by the easiest means available. Your narrow definition of profit is seldom the easiest, cheating is far "superior" especially when it's legal for some.

> None of this requires taking anything away from any other party.

"required" and "preferred" (e.g. because it's far easier) are different like night and day.

Trade is just a combination of give and take. I give you X, and in exchange, take Y. Without the "take", it's not a trade, it's just a gift.