^ When buying sold by Amazon (not 3rd party) I have never gotten fake parts, though they have the same situation as Rock Auto that sometimes you pay more for what you think is a premium part and just get the same thing sold for less under a different brand, in the premium brand's box.
Rock Auto deceptive or lying? Maybe, or maybe turning a blind eye towards a shipping algorithm bug that works in their favor, and yet, it doesn't necessarily work in their favor if they are shipping from multiple warehouses and having to pay for that instead of fewer warehouses. Now if they charged for multiple warehouse shipping THEN shipped it all in the same box from same warehouse, THAT would be more ****ing.
Amazon is shady in some ways too. The irony is we are contrasting these two when they are the two cheapest, consistent retailers of parts. I order from both, and have 100% satisfaction from neither, but overall come out ahead from the cost savings even if a few problems come up from time to time. Depends on what the item is too, the more likely something can go wrong, the more likely I'd get it at Amazon for easier and cheaper return shipping.
I would buy from Rock Auto every now and then even if it cost a little more because they are the best automotive parts resource for DIYers that the world has ever known. The amount of parts, their website database presentation is 2nd to none. It's funny that Amazon could compete with that in a different way if their reviews were detail oriented about automotive parts but for some reason amazon reviews about automotive parts are conspicuously pathetic, with many reviewers not even mentioning what vehicle they have. Granted a fair % of the Amazon reviews, particularly for generic parts, may be fake with the reviewer having no clue about the item.
I do think Rock Auto's customer service is poor, but I recognize that good CS costs money. Overall I have come out ahead at RA despite having to return (or eat the loss) on a few things, but if you really want the lowest cost, it is near impossible to beat Amazon warehouse parts, if you get lucky and find what you need, when you need it. Part of that is not being super picky about which brand it is.
Then there is the warranty which you lose out on with some Amazon warehouse parts, and even if a part was sold new retail at Amazon and showed a warranty, good luck getting Amazon to honor it. They refer you to the manufacturer who then refers you back to Amazon stating it is the retailer who handles that, then the Amazon CSR refers you back to the manufacturer. Apparently they don't have a way to put that into their system or something, set up that way deliberately.