I realize it's a joke and I should just laugh, but since a couple of people asked in a way that seems to want a serious answer, and since I'm a foreigner living in Germany who feels like I can contribute a meaningful answer… Germans do take work-life balance very seriously, to the extent where working overtime is sometimes seen as being suspect rather than laudable. (It's often seen more as "Why does that person need to work longer hours? Are they not managing their workload properly?" rather than "What a great example of a work ethic!") The reason why this stereotype is somewhat true is reflected by the previous comment about all the "Simualator" games which prevail in Germany: even in their leisure time, Germans like to do things which are personally productive, whether it's reading a book, doing some kind of athletics, or voluteering for some environmental/social cause. Although the Puritans were English rather than German, Germany has some kinship with that movement in that Germans seem to think that being lazy is bad for your personal character. It says something, I think, that a country which is mostly famous for sausages and beer has relatively few overweight people.

TL,DR version: You remember "Work hard, play hard"? Germany is like that.