If you don't get fakes, you can get QC rejects, which may be genuine parts but sent to "recycling" for not passing spec.
They could also be pulls, or leftover reels.
I've gotten all of the above.
More reputable suppliers will be able to source working chips, maybe with old date codes. You can get a decent savings in this way.
In general when working with a chinese supplier I would follow the same formula to minimize risk and maximize gain:
1. Order small volume (10-50) - you should get genuine chips no matter the shadiness of the supplier. If you still get fakes at this point go no further.
2. Double order size, that is all. Date codes may be older or they may require bakeout but still be legit.
3. Continue to double order size to your target, instead of buying your target quantity directly.
Around the 5th order, no matter what volume is where you want to be careful. Maintain vigilance and ensure functoinality of your parts. If you get fails/fakes tell them so, and tell them they need to exchange for genuine chips. You'll probably be delayed/ignored for a while which is where you want to find a different supplier and repeat the process.
Also, a supplier's success in sourcing 1 particular chip will not necessarily carry over into finding other items - caveat emptor.