Its not a business, its just easy extra cash. Bought a bag of ---steaming pile of meadow muffin--- bearings for cheap, filament is cheap.
Plus its all about the salesman

people can buy china ones OR they can buy custom made in the USA right now from me. It mostly been around the office, call centers love them.
I can usually get 10-20 bucks for each one, Here is a cool
Punishertheme one I just designed for a coworker.