Walk through shopping centers in different states during the holidays and the same recordings recur. The repetition is a licensing and merchandising outcome rather than a shortage of seasonal music.
Stores license from services, not albums
Playing music in a commercial space requires rights beyond those covering personal listening, so most chains subscribe to a background music service that handles the clearances.
Those services build seasonal channels from catalogs they have already licensed, and the overlap between providers is considerable.
A store is therefore choosing a channel rather than songs, and the channel's contents are shaped by what was economical to clear.
Tempo is chosen for the floor
Background music in retail is selected partly for pace, since tempo influences how quickly people move through a space and how long they linger.
Holiday channels are assembled with that in mind, favoring recordings that sit in a comfortable range and avoiding anything abrupt or sparse.
Many seasonal songs are excluded not for taste reasons but because their arrangements do not sit well underneath conversation.
Familiarity is the point
Seasonal music works commercially by signaling the time of year immediately, and only widely known recordings do that within a few bars.
A new holiday song, however good, requires repeated exposure before it carries that association, which is why the canon changes slowly.
The handful of additions that have joined the rotation in recent decades did so through years of annual play rather than through a single successful season.
Public domain versus recording rights
Many traditional carols are old enough to be free of composition rights, but every recording of them is a separate protected work.
Services can commission inexpensive new recordings of those carols, which is why unfamiliar versions of very familiar songs turn up in stores.
Songs written in the modern era carry both composition and recording rights, making them costlier and consequently rarer on background channels.
The season starts by inventory, not by calendar
Retailers begin seasonal music when seasonal merchandise reaches the floor, which is governed by shipping schedules and shelf planning set months earlier.
That is why the music can begin well before anyone expects it, in a store where the holiday aisle is already built.
The soundtrack is part of the display, timed to the same plan, and it ends the moment that merchandise is cleared for the next season.