Thanks for your reply...
Have friends European pilots and when they jumpseat EU-DR and DR-EU pay zero, not even international taxes.
Supposedly airline collects the tax on behalf of a country for each TICKET SOLD and at the end of the month submits the payment for tax X number of tickets sold to the foreign government. Since actual jumpseat is not for sale and airline collects jumseater's int'l tax, such tax will never be paid to the country. Hence extra $$$ stays with the company.