I am afraid that is how it's going to be. I have found that there is no rhyme nor reason as to what they charge. It seems to be what they feel like on the day.
I had a packet from the UK via Correos with a contents value of about £4 and had to pay €10 to get it. If I hadn't actually need it I would have told them to stuff it.
One last week from the US, contents 6$ and later got a separate bill from FedEx for €10-01 PLUS IVA.
Wherever possible I now look on European sites, but be careful on Ebay as some of the goods still come from the UK, so you will get stung. It always says on Ebay where the goods are coming from.