What\u27s the Harm of Trademark Infringement?

For decades, the concept of actionable trademark infringement has been expanding. Source confusion, reverse confusion, approval/affiliation confusion, initial interest confusion, post-sale confusion, endorsement confusion, and so on, all have won cases for plaintiffs. Whether or not the confusion cost the plaintiff any sales, or was in any way material to consumers, our concept of trademark infringement now encompasses it. These expansions occurred for reasons that seemed sufficient to courts at the time, when advocates offered theories about how all these kinds of confusion could cause harm to the trademark owner. Primarily, courts feared that non-competing uses would preclude trademark owners from expanding into natural markets or tarnish its reputation among its existing consumers