The idea that you can return unsold product to the supplier is a relatively new idea for most industries. When retail boxed software was at its peak (in the 90's), it wasn't very common at all.
I can't find anything current for boxed software (for obvious reasons), but boxed video and board games cannot be returned unless the retailer has a special deal with the publisher (rare).
It's not how the mass market book and (I assumw from your other link title) at least popular recording industries work, but it's how lots of the rest of the physical retail industries, including IP-based ones, work and have worked, and a big part of why (for instance), TSR (the original publishers of D&D), who sold IP-based products (including books) outside of the mass book trade was completely unprepared for the “success” of getting it's books into the mass book trade, where failing to adequately account for costs of remaindering almost drove them out of business before Wizards of the Coast bought them for the IP.
Apple act as a middleman and and add on their fees, with absolutely no risk to themselves.
They're very different business models.