Somewhere out there, advertisers are paying dollars for those commercials, and in many cases no-one is listening, or worse - it's causing active irritation to the people who are.
If you think of the commercials as oil, and the speaker systems and infrastructure as pipelines, then cases like this where commercials are on incessant loop are like an unbridled oil spill.
Unfortunately, many advertisers likely aren't metric-savvy enough to realize they're being scammed and not getting a return on their investment; the folks selling the airtime likely take a skim of their deals and use it to wine and dine the advertisers' own staff.
Purchase and persuade one or two layers of staff and management, and you're unlikely to get too much organizational pushback.
Instead, there should be costs placed on the measurable negative externalities here: the stress caused to people who experience this noise pollution, the devaluation of the otherwise quiet, productive environments it seeps into, and the opportunity cost from the resources wasted on building the infrastructure to make it possible in the first place.