Originally Posted by
WorldLux
Slightly incorrect. AFAIK, customs inspections take place both when entering the Schengen area and when arriving at your final destination within the Schengen area.
Nope, there is no need for that, and there is no customs desk (empty or not) after transfer immigration, since there will be one once you try to get out of the airport.
Even within Schengen, there are import restrictions, and each country has their own restrictions, therefore there is no point in declaring in Germany something you are importing to Poland as the rules may differ.