Tax Cuts for European Catholics!

I had never heard anything like this before. Is it possible that one reason American Church attendance is up and its charities are more flush than European ones is because tithing is voluntary? From John Allen's report from WYD yesterday, something astonishing.
In recent years, the number of baptized Catholics who have officially left the church in order to avoid paying the mandatory kirchensteuer, or "church tax," has risen to such levels that the bishops' conference has warned of serious financial shortfalls.
Historically, those tax receipts have allowed the Catholic church in Germany to operate a vast network of institutions, including schools, hospitals, clinics, social-welfare agencies, day-care centers, and charitable organizations such as Caritas, Missio, and Adveniat. As a result, the church has been the second largest employer in the country.
Benedict XVI has sometimes criticized this massive bureaucracy for being self-perpetuating, even after its original purpose has been outlived.
Too bad Jack Kemp's not Catholic. We could send him to teach the European bishops about supply-side economics. First rule: when you tax something, you get less of it.