I think a lot of trademark law could just as well be replaced with existing law against fraud and defamation. The fake Apple stores in China which sell inferior

I think a lot of trademark law could just as well be replaced with existing law against fraud and defamation. The fake Apple stores in China which sell inferior knock-offs are defrauding their customers who bought thinking they were buying a quality Apple product but instead ended up with a product merely masquerading as an Apple product. So the customers would have a fraud action against the fake Apple stores. Also, by selling inferior "Apple" products, the fake stores are harming Apple's reputation. This would give Apple a defamation case against the stores. Such a scheme would have the added benefit of encouraging quality products to the point that companies producing poor-quality goods could lose their trademarks to quality companies. So if Dell began producing their own line of "Apple" branded computers, Apple could only sue Dell if the Dell "Apple" computers were causing harm to Apple's reputation. If Dell's computers were actually better that Apple's computers, Apple would have no cause of action. In time, if Dell could show that Apple's computers were actually causing harm to Dell's reputation, Dell could force Apple to pay damages for using the Apple mark.