It's a bit bizarre and unconsistent. Everything went well in my case (Germany), I got an email with a tracking number and it was delivered the next day. However it's strange to read that people outside EU have to pay some handling fee to UPS, bearing in mind that delivery was announced as free.
That's not bizarre at all - it's the law. Customs duties and extra shipping agent fees for imported items outside of trading regions is to be expected. UPS are charged by customs and they pass that cost on to the receiver, plus their own levy.
Flare were perfectly correct in saying delivery was free - they didnt charge any extra for it. Beyond that, its out of their control.