Not too long ago, I had a lovely encounter with customs in the EU who went through ALL my stuff and demanded receipts for anything that looked remotely expensive. They finally hit the jackpot when they found one item that apparently wasn't bought in the EU (read: I was unable to prove I had bought it in the EU). Had to pay import duties and taxes, and the customs agent made sure to inform me that if the tax amount had exceeded 250eu, they would have initiated criminal proceedings for tax evasion.
And some people still think they're after the big fish...
I also have︀ to say, that I have not found any grounds for that 250eu claim. Even when︁ demanding for more information. But they would have gladly taken that item anyways and left︂ me to figure out the next steps