The device is not 'just audio'. 

On the schematic in the data sheet you link to, you will see that there are as many small capacitors shown as there are power pins on the rail. That's a convention to mean that each power pin needs a capacitor, mount them as close to the power pin as physically feasible, and with a short connection to the correct ground as well, usually just the appropriate ground plane. This is so that the logic parts of the chip have an electrically 'stiff' supply on every pin. That's so the digital pins can draw their current steps with rise times of ns without disturbing the supply. These capacitors are in addition to the larger caps you have near your regulator.

Do you need them at all? Why not try without, it may well work.

How much would you save by leaving them out? A few pennies, and a few mm2 of board area.

How much could it cost you to leave them out? 
- It could cost you another spin of the board when you find you need them, and weeks of delay. 
- It could cost you weeks of troubleshooting to find out why things aren't working. 
- It could cost you *months* of troubleshooting if things don't work but just from time to time. 
- It could cost you customers if things work in the lab, but don't work when delivered to the field, that's a very nasty one.

It's your call, but I would put them in.