Almost universally
This is how commercial laundries process eiderdowns, duvets, pillows, and similar items.
As for the cost, well you have to take into account labor, machines, chemicals and yes the fact down filled items (if done properly), take ages to dry fully.
That being said better quality places will take things a step further. Things are examined for stains/pre-treated, higher quality and proper chemicals suited to down, etc... OTOH have seen the Chinese lad at local laundromat simply bung a eiderdown into a washer, set it for "hot" and add Tide with Bleach powder.
In theory drying down or feather filled items calls for a dryer to be set on "low", and the things need enough space to move about freely especially as they dry and fluff up.
What you get with a commercial washing machine is robust bearings and suspension systems that can with stand the abuses that come from washing heavy bulky items. Yes, many can and so launder such things at home rather successfully, but ask any appliance repair person or dealer about what happens when things go bad. Even Miele residential washers have been destroyed by just one down or pillow washing gone wrong.