For cooks and chefs perhaps, but not for the entire workforce. Then again, the hospitality sector has a knack for abusing their workers, so I wouldn't be too surprised if they make waiters work for free as a "trial" as well.

It's still silly to expect to have to work for you for free. You can discuss technical topics (design experience, programming language preferences, etc.) without doing a whole exercise. Honestly, it's insulting that people will ask you to come in for an interview and basically tell you that they don't believe what you've put on your resume and start quizzing you to confirm that you know what you claim you know.