They are very much meant to be bought. And you may even receive an item that resamvles what shown on the photo.

I remember buying a fake card from ebay, it was many years ago. It had fake amount of VRAM and fake identifier (it was promised to be from 1xxx generation but actually was from 4xx). The seller kept offering me refunds on each of my complaints incrementally, starting from 20%, eventually they even offered 90% refund, but I still refused.

In the end, eBay itself gave me full refund from the seller since the seller never provided return address details even though kept promising to provide it to stall for time in the hope I give up (ebay required me to request return address). After all the years, the fake card is still used by one of the family members who does not need high-end GPU, and just uses the PC to browse the web ro watch videos.

But obviously there is always a risk that you don't get refund and end up with fake item. In this case, you are guaranteed to receive a fake Mac, and the seller will do anything to trick you to agree to a partial refund and get away with your money.

This is one way how these scams work. There are many variations, like selling only the box instead of the item and then claiming you bought just a box, or not shipping at all and give fake tracking number, or even shipping something entirely different that approximately matches expected weight in the hope you make mistake of accepting the package without hacking the content and open it without making a video where it is always in view (to have a proof that you did not replace the item yourself).