Jacee,
All knots are bleached at the factory. The darker the hair the more tricky it is to bleach. Dye too much and it weakens the knots. Dye too little and the knot does not entirely disappear. The darker the hair the longer the knots need to be bleached. And dying the #22R hair darker by yourself is also tricky--get some dye on the base and you'll have a tough time removing the dye. Hersute brings up a good point---f you have has more than one color in it how are you going to bleach those colors into #22R? I'm not sure what the pay rate is for workers in China but I can tell you that we as hair wearers are the beneficiaries of extremely low labor rates. Cheap labor is the major component that makes hair wearing affordable for all of us. If units were made by American workers making the bare minimum wage the cost of a hair unit would be 'through the roof.' We're very lucky to have access to cheap labor.
Regards,
John