I've flown through the next INTL airports on "domestic(EU)" flights and on international flights :
- Barcelona - El prat T1
- Barcelona - El prat T2
- Madrid - Barajas T2
- Madrid - Barajas T4
- London - Luton (unkwnown terminal)
- London - HTRW T3
- London - HTRW T5
- London - HTRW T4
- Brussels Zaventem (unkown terminal)
And so far my experience has been that EU as a whole doesn't really care about what individuals take in/out as long as it's legal*.
*legal : no knifes, no drugs, no big filled bottles, no live animals, etc...
Why?
Completely personal opinion, i'm no lawyer, but from my POV, the human and technological cost of stopping James Notfakename from bringing a pork sandwitch into europe or an ipad from hong kong is way too high to even care, the effects on the economy will be completely unnoticeable if that horrible sandwitch sneaks security, and even if you managed to disguise something like a toad, the EU has so many varying ecosystems in the 28 member states that yet another invasor animal won't hurt, also the ecosystem here is stronger than in some very complicated places like australia, where leaving two rabbits alone can lead to rabbitgeddon. the TSA thinks otherwise though and threw my EU regulated, air-sealed, purchased on the duty-free zone, pack of deer butcheries.
waves fist on air angrily...
how do they catch someone if there is no one there?
People must pass X-rays, cameras, bioscanners and dogs.
of course, sneaking a small bag of pot from a local airport to another can be easy, but as soon as you reach some INTL airport chances are they already know even your underwear size once you cross the gates.
How do you know what to declare when you are not given a form?
There are big, multi-language walls on the airports telling you what you should declare, what items are banned , and what needs special sealing to get in.
EU law also works differently than in USA; not knowing a law/regulation doesn't mean you don't have to follow it.
Example : We've got no miranda rights statement here, everybody should know their rights and duties beforehand.