Two mattresses can be the same product with different names and different prices, and a shopper has no straightforward way to establish that. The opacity is a feature of how the category is sold rather than an accident.
Exclusive model names break price matching
Manufacturers supply the same construction to different retailers under different model names, sometimes with a cosmetic change to the cover fabric.
Because the model numbers do not match, a price-match guarantee cannot be invoked and an online search will not surface the same bed elsewhere.
This practice is widespread enough that identical names across two retailers are the exception rather than the rule.
The specification that matters is not on the label
What determines how a foam mattress performs and how long it lasts is the density of the foam layers, measured as weight per unit of volume.
Density is rarely printed on the label. Thickness, layer count and marketing names for proprietary foams appear instead, none of which indicate durability.
Two beds described identically in inches can therefore contain very different material, with the cheaper one softening far sooner.
Comfort language has no fixed meaning
Firmness ratings are set by each manufacturer against its own range. A medium in one line can sit where another line places a firm.
There is no industry scale behind the terms, so the words describe a position within a catalogue rather than a measurable property.
Body weight changes the experience further, which is why the same mattress genuinely feels different to two people and why in-store testing is a weak signal.
Prices are set to be discounted
Mattress retail runs on near-permanent promotions tied to holiday weekends, so list prices are constructed with the discount already anticipated.
A high stated price that is always reduced serves as an anchor, making the sale figure read as a saving rather than as the intended price.
The practical effect is that the list price carries almost no information, and comparisons based on the discount percentage are comparing invented numbers.
Trial periods shift the real cost
Because a mattress cannot be judged in a showroom, sellers offer home trial periods, and a returned mattress usually cannot be resold as new.
The cost of collecting and disposing of returns is carried in the price of every mattress sold, whether or not the buyer returns theirs.
Reading the trial terms is therefore more useful than reading the specification, because the return conditions, collection fees and restocking rules are the part that is actually enforceable.