IIRC, this embellishment comes from a tabloid story about a woman who refused a job as a cleaning woman for a company that also had a contract with a brothel and then had her unemployment benefits reduced. Seems people now only remember the sensationalist headline ("Woman Refuses To Work In Brothel, Has Benefits Cut")...
“A 25-year-old waitress who turned down a job providing “sexual services’’ at a brothel in Berlin faces possible cuts to her unemployment benefit under laws introduced this year.”
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“Under Germany’s welfare reforms, any woman under 55 who has been out of work for more than a year can be forced to take an available job – including in the sex industry – or lose her unemployment benefit. Last month German unemployment rose for the 11th consecutive month to 4.5 million, taking the number out of work to its highest since reunification in 1990.
The government had considered making brothels an exception on moral grounds, but decided that it would be too difficult to distinguish them from bars. As a result, job centres must treat employers looking for a prostitute in the same way as those looking for a dental nurse.”
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“There is now nothing in the law to stop women from being sent into the sex industry,” said Merchthild Garweg, a lawyer from Hamburg who specialises in such cases. “The new regulations say that working in the sex industry is not immoral any more, and so jobs cannot be turned down without a risk to benefits.”