[AdamJacobMuller]

Amazon credits you when someone buys your item, but the item Amazon ships the buyer might not be yours, but an equal equivalent.

And, before you ask: Yes, this results in situations where 100% legitimate sellers on Amazon can sometimes ship (via Amazon/FBA) their buyers counterfeit goods. Shitty situation to be in as a seller.

[cookiecaper]

Sellers can opt-out of commingling, but many don't because a) they don't understand the implications, as Amazon doesn't really make it clear; and b) because it requires them to individually add a separate sticker/identifier to each unit of their product, adding significantly to preparation and packaging costs.

[AdamJacobMuller]

I think Amazon charges more for storage fees if you disable commingling too.

[cnst]

I'd imagine fulfillment would be pricier, too, since items could no longer be located at every warehouse at no extra effort.

[throwawaylalala]

Not correct. They do however make you pay for a tier above their "small and light" for handling.

[throwawaylalala]

Not true; depends on whether or not you use comingled inventory. It's easy to make it not comingled. That's what we do.