on to say: The purpose of the passing‑off action is thus also to prevent unfair competition. One does not have to be a fanatical moralist to understand how appropriating another person's work, as that is certainly what is involved, is a breach of good faith. However, the action of passing off (and the law of trademarks in general) is not a substitute for unfair competition laws. The Supreme Court noted in a subsequent case, Kirkbi AG v. Ritvik Holdings Inc. (popularly known as the Lego/Mega Bloks case), that "the purpose of a trade-mark ... is the protection of the distinctiveness of the product, not of a monopoly on the product." Furthermore, "trade-marks law is not intended to prevent the competitive use of utilitarian features of products, but ... fulfills a source-distinguishing function." Protection for consumers While the law of passing off historically developed to protect sellers of goods and services, it has also taken on a dimension of consumer protection. In Mattel Inc v 3894207 Canada Inc (a case involving the Barbie trademark), the Supreme Court commented on this aspect: However, whatever their commercial evolution, the legal purpose of trade-marks continues (in terms of s. 2 of the Trade-marks Act, R.S.C. 1985, c. T-13) to be their use by the owner "to distinguish wares or services manufactured, sold, leased, hired or performed by him from those manufactured, sold, leased, hired or performed by others". It is a guarantee of origin and inferentially, an assurance to the consumer that the quality will be what he or she has come to associate with a particular trade-mark (as in the case of the mythical "Maytag" repairman). It is, in that sense, consumer protection legislation. Due to the nature of trademark law as a consumer protection measure, there is some debate as to whether "post-sale confusion" (as in the case of a consumer knowingly purchasing counterfeit goods but fooling others into thinking they are the real thing) should be an actionable trademark infringement or considered under the tort of passing off. Some observers suggest that trademark law would be better served and more consistent by making post-sale confusion an actionable infringement. Others suggest that post-sale confusion should not be actionable, or that other laws may be better suited to protect manufacturers from counterfeit goods. In Canada, post-sale confusion is not a cause for action under either the Trade-marks Act or the common law tort