Why Some Items Can't Be Comparison-Shopped
Exclusive product lines, private-label goods, and certain direct-to-consumer brands are sometimes only available through a single retailer, which removes the ability to cross-check the claimed 'original' price against another seller's listing.
Falling Back on Category Benchmarks
When comparison shopping isn't possible, a category-realistic discount range becomes the primary tool for judging plausibility, since it doesn't depend on finding the exact same item listed elsewhere.
Weighing the Lack of Comparison Itself
The complete absence of any comparable listing anywhere is, on its own, one of the recognized signals worth factoring into an overall assessment, since it removes a layer of verification a shopper would otherwise have available.
A Reasonable Approach for Exclusive Items
Combine the category benchmark check with a broader look at the brand's general reputation and return policy, since these secondary signals can help offset the missing ability to directly compare prices.