Exchange is no robbery.

A voluntary, informed swap is not theft: when each side freely agrees to trade, neither has been robbed merely because something changes hands.

The saying may answer a complaint after a bargain, stressing mutual acceptance rather than unilateral taking. It does not justify a deal obtained through coercion, deception, or a serious imbalance of choice or power.

Use it when defending a genuinely consensual trade or bargain against an accusation of unfair taking. It can sound dismissive, and should not be used to minimize a complaint about an exploitative exchange or one in which consent was not meaningful.