You're shifting the goalposts. Presenting misinformation to consumers is generally illegal, and is also a completely separate concern from copying and building off of others' innovations. I haven't seen any comments here that support outright tricking unsuspecting customers into accidentally buying a cheap knockoff when they were looking for a higher-quality original.
A common misconception creatives tend to have about business is that it's 100% about crafting a unique and/or valuable product or service. It's not. There are innovations and competitive advantages one can have in distribution, sales, branding, pricing, and many other areas. These can also drive business success, and it is not scummy or dodgy to put them to use.
Some products are naturally defensible (e.g. the network effects of a social network) and some are protected by copyright and other laws (e.g. writing, photos, and logos, but not clothing or, in this case, shoe design), but the vast majority are wide open to competition, and it's your job as a business owner to either figure it out or avoid those industries.
You aren't automatically entitled to overall business success just because you were the first to do X or you worked the hardest on it. Doesn't matter if it's wool shoes, v-neck shirts, autotune in your music, customer support chat widgets, a mobile operating system, or like buttons in your social app. Just because you're a designer who likes designing and works hard at it doesn't make design a defensible business strategy in your industry.