When it comes to green, red or any other dealer branded filter is is just the volume thing
Auto shops get filters in big boxes often several hundred at a time every week
Mower shops usually only stock retail boxed filters and would be lucky to buy a carton of 24 a month
The filter factory makes filters in batches of "economic size" so may only do 1 run of JD, Toro, Hustler etc etc filters a year
SO the mower companies have to buy the filters in lots of 5,000 to 20,000 .
These have to be paid for as they leave to dock, taken to a warehouse , stored, picks & despatched to local distribution centres then finally to the dealer.
All of this adds substantially to the cost
My wholesale for retail boxed filters is $ 14 each while a trade pack of 12 boxed filters goes down to $ 11 each , a workshop pack of 24 unboxed drops the price to $ 9 each and a manufactures pack of 144 drops the price to $ 5 each .
Warehousing & logistics add a lot more to the price of goods than most outside the transport industry would believe .