If someone is willing to pay extra for an identical product because it's made by a more famous company they have only themselves to blame.

How long must one keep his IT infrastructure as cattle instead of pets to come to believe that such a thing like an „identical“ product exists? :p In the real world almost nothing is fungible. Additionally, even with white labelling there is value created (look at Xiaomi for an example).

Have you met humans? Most status-symbols are all about the brand name, identical products made by other people don't count.

And im ok with that. If someone makes a shitty knock-off,i dont think the original manufacturer should get the blame.

> shitty knock-off

I wrote "identical"

Sure, it's also their choice. I wouldn't buy Nike trainers or Levi jeans, but I'm sure some people do, and by taking away that choice you are stealing from them.

What choice am I taking away from them?

The choice of where to spend their money - if they choose to spend it with Adidas, despite you and me thinking the product is terrible, and a far cheaper copy is better - that's their choice. By preventing them from knowing where the money is going, you are harming the consumer.

This is different to copyright or patents where the consumer is prevented from buying the alternative.