I live in Germany and pay between 20-25% of my income in income tax depending on how much I bill. I easily support a family of 4 on this. Rent, car, holidays, the lot.
I believe, when you are employed, you must also pay pension insurance, unemployment insurance, health insurance and other. No way you will be at 20-25 percent in Germany.
When you count employer contributions, then you are quite close to 50%.
According to Wikipedia, if you pay 25% income tax in Germany you make €50 k, which doesn't sound like a very comfortable family income, unless you live in the country side perhaps.