I agree, take it back
They have a great return policy, I've even taken back open wine.
With the cinnamon I'd already made a batch of cinnamon sugar with it, and well it was only something like $4 (you get what you pay for), but it really does have an off taste and it's suppose to be the same type of standard "cinnamon" you get at the supermarket. I checked before I bought it.
I'm still working on my huge bottle of vanilla I got a smart and final, but I doubt they still carry the same one.