In the Netherlands, they finally caught a Romanian who had registered for welfare under 15 different names, and only got caught when some case worker noticed that he kept coming in ever more expensive cars each month. The penalty for unarmed theft in this part of the world, is usually a slap on the wrist and "bad boy, don't do it again (they will)."
My wife, when she was active as a social worker, wanted to strike child money benefits for a Lebanese immigrant in Duisburg, the center of the Lebanese mafia in Germany. He at first got an apartment for him and his "wife," and never showed up for work or appointments, saying he didn't feel good. He did, however, feel good enough to rent a second apartment, where he lived by himself, while his wife and 15 children lived cramped in the apartment next door. He went to court to save his benefits from being stricken. The social services showed up with one lawyer from the social services. The Lebanese guy showed up with three well dressed lawyers from a big fancy firm and about twenty big bouncer-types in the public, making evil faces at the judge--all the while claiming to be a poor, helpless welfare case who was being dumped on unfairly. The judge got the message, cut short the testimony from my wife and the other social worker, and decided for the Lebanese guy.
Billions in taxpayer money disappear here, too, and to similar schemes, and for the same reasons. To the perps, it's here for the taking, and if the Europeans don't stop it, well, that's their fault. The difference is that here, no one ever goes to jail for it.
And THEN they wonder how come the anti-immigrant far right party gets increasing numbers of followers. It boggles the mind.