The same most definitely happens with real apprenticeships. In countries like Switzerland, apprenticeships start after the 9th school year and take around 3 to 4 years. During the apprenticeship, the apprentices still have to visit school and write tests. This is a common point of conflict. Let's imagine you are a 17 year old who wants to become a cook and your boss makes you clean the kitchen until 2am and the next day you have a test on algebra at 7:15am. There are laws against this kind of stuff but enforcement is really spotty.