Earlier quoted context omitted.
>passed through customs Your vendor selected to bill the duties and taxes to you.
Then why did FedEx explicitly told me that the 50EUR was the charge for the paper to pick it up and not for the package itself ? Why did the customs told me that there was no charge for books and that anyone with the paper for the package could pick it up free of charge ?
By FedEx i mean "Rangel Expresso SA" (www.rangel.pt or www.fedex.com/pt) which is their representation (Global Service Participant (GSP)) here in Portugal.
By customs i mean airport customs (the ones i contacted), not the portuguese state customs. I don't know how they evaluated the package, they probably didn't even knew about it (due to lack of staff or other stuff...).