In Chinese factories, some OEM suppliers do make extra unapproved batches and sell them on cheap to the local market. However, the items are either identical in every respect, or may have labels changed.
If the item does not look the same physically, like the servos in the OP, they probably came out of a different factory and are not at all related to the original product.
Having said this, I see that I too have bought fake Futaba servos in China. One sail arm servo died, another regular servo is still going fine after 8 years.
From my experience, most Chinese stuff is now OK quality, probably better than the 1970s Made in Britain (being brutally honest). The issue is paying the brand premium for Futaba etc. when only getting lesser branded product, and you get no aftersales care.