Because from my limited understanding, it allowed them to easily participate in further vocational training to become well paid specialists or leaders. In addition, the support system was such that there were numerous opportunities across the Mittelstand, whereas in the USA is easy for dropouts to be stuck flipping burgers long term without support or guidance to turn their job as fry lord into a career or job that is more...sustainable.
Not all of those apprenticeships are high level ones and I suspect there is much less possibility of starting as an apprentice and going all the way to a degree as say Mech Eng apprentice at BAE Systems might.
This is the route I took BTW.
I have had interviews just stop dead (with European companies) when it turned out I didn't have a Degree.
