You don't generally have to trust. If you do your research you can buy a counterfeit of the highest quality which is often better than the product.
There are counterfeits that are of low quality, with a suitably even lower price, but by doing some research you can often tell.
This is a big problem for sneakers, counterfeits are often literally impossible for anyone to distinguish. In my high school a kid would be selling knock offs of hyped shoes and brought them to official stores or specialized resellers and got them appraised as authentic, repeatedly.
Now I hear through the grapevine that they have to use things like the rigidity of the cardboard in the box they came in with to try and figure out fakes, because the shoe itself is just too close to tell.
Ultimately there's nothing magic to the original. The products are generally much cheaper to make than they are sold, so there is no reason why someone couldn't make a version with better materials at the same cost. It's a question of imaginary property and signaling more than anything.