Most likely this is exactly what happened. Highly doubt this was intercepted and stolen, dude got the product, put weights in and claimed fraud for a huge pay day, knowing newegg has been under fire recently. Scamming 101. I could absolutely be wrong, but the odds weigh heavilly in my favor, 1 billion orders not having this issue vrs this guy.
The lack of evidence of those weights banging around is 100% the clencher here...that coupled with noone thinking anything was funny with this package.
The fact that the weight was consistant is again 100% nails in the coffin, it would be off slightly if not hugely.
That's not what happened at all. You all have to think: If someone is going to be pulling off this scam, they're going to be thinking it through. They know the "sTeAl ShOuLd MaKe DeNtS iN tHe FoAm InSiDe ThE bOx", and eagle-eyed people will notice that. They know that the weights should "mOvE aRoUnD iNsIdE tHe PaCkAgE aNd MaKe NoIsE".... and that newegg inspects things, as well as weight discrepancies, etc etc.... Keep in mind, the photo you have of the weights is the one the purchaser took. Its very well possible that the box didnt contain just two steel weights free-floating, but probably contained other items to hold the weights in place, suppress their movement, and maintain the same weight as the GPU would. Let me break it down to you slowly. Here's what happened:
Step 1) Person orders 4090, receives it, weighs it, takes note of weight.
Step 2) Person with surgeon-hand precision very carefully unseals it, making sure to do as little damage to the box/seal as possible, pulls out the GPU
Step 3) Person stuffed it with weights and other objects to suppress movement, weighed it again, made sure it was an EXACT match within a gram or two, very carefully sealed it up so as to look as though it had never been opened, then returned it to newegg, made some reason to return it that they know most retailers accept.
Step 4) Newegg receives return, weighs it, feels it, inspects it, can very clearly tell that the box has not been opened (even though it has)
Step 5) Newegg warehouse workers put UNOPENED (so they thought) GPU back on shelf for sale, sends refund to customer who is actually a scam artist
Step 6) Another person orders GPU, warehouse worker grabs UNOPENED (So they thought) GPU off shelf, ships it to customer
Step 7) Customer opens box, 2 weights in place with other objects, likely styrofoam or something to suppress movement, pulls out said objects, and takes photo of 2 steal weights
Don't slam newegg for not checking the box. Of importance here is the following: When a customer receives a new purchase, they expect it to arrive sealed, unopened. Isn't that what you would expect? If you dropped down $2000+ on a 4090, and the seal EVEN LOOKED LIKE it had been tampered with, POSSIBLY OPENED, you might return it, maybe? Some people do. You want that seal untouched, like it was from factory so you know you are getting a new card. You just spent $2000+. Hello???? This is why in step 4, Newegg doesn't open the box to check, because they know that any customer who buys it will want to see the seal untampered, and the scam artist made sure to make it look like the seal had been untampered. If they open it, and everything is legit, now its been opened, and cant be resold as new, and has to be sold at discount as open box. Is this making sense? Are you getting it now? Come on, its not that hard. You have to think about all these things but no one seems to think about this.
The only fool proof solution here: Is for receivers of returns to be able to X-Ray boxes of every return. Why this isn't being done, I dont know. But it should be.