I don't know how effective the wording of the original consignment agreement would end up if tested in a suit. It reads "Consigned merchandise shall remain the property of Mansell until sold".

On the other hand, without the agreement, how can one prove the expectation that the goods were handed over with, at all? Without establishing that expectation wouldn't the ownership of the goods just stay with the original owner at all times?

It would make sense that there are some ways you can abandon property you own in a way that someone else can swoop up and take ownership it without having to give it back, but do any of those potentially apply here?

> The store obviously has an obligation to hand over either money or the goods, but it's not clear that obligation is transient to anyone that ends up with the goods.

It is extremely clear. You are just detailing the buffer being used to pretend otherwise.