A hotel mattress is specified by how many nights it has to survive, not by how it feels in a showroom: pocket springs under a replaceable topper, because the topper is what wears out and the springs are what you are paying for. Vacuum-rolled, so one pallet carries a floor's worth.
The topper takes the wear and the stains and costs a fraction of the mattress to replace. Housekeeping swaps one in minutes; replacing a mattress takes the room out of service.
Vacuum-rolled and boxed, which is what makes a floor-by-floor refit possible: a lift takes a pallet of rolls where it would not take a load of mattresses. They need a day or two to recover full loft before a guest sleeps on one.
Medium-firm disappoints the fewest people, which is the real goal in a room you cannot tailor to the guest. Where a floor can be split, a firmer option on a few rooms covers the ones who ask at check-in.
