When I first moved to Germany I registered with the Social Services and got a tx number etc as I wanted to start work straight away. I was asked my religion and said "evangelisch" be ause I didn't think she'd know what "anglikanisch" was. When I got my first payslip I saw that the church tax had been deducted. As I had married into a Catholic family, I was a little taken aback at this and went along to the relevant office to correct the mistake. So I haven't paid church tax since. If I could, I would, as they run kindergartens, hospitals, care homes and many other social institutions.
The Catholic church has shot itself in the foot with the recent coming to light of scandals such as abuse and corruption and many have left the church because of this (including at least one of my sons). Even our local parish has had its stories.
It A difficult situation.
BTW, nanna8 whether you pay the tax has nothing to do with church attendance. Those who do attend give additionally with their time, money, and any other skills they can offer, such as with music, visiting the sick, baking cakes etc. As was stated above, church tax is deducted directly from your salary - there is no check on attendance, no roll call.
If you are not Catholic but wish to marry one in a Catholic church, you can ask around and you will usually find a priest who will perform the ceremony. Not all do, but this is up to the individual priest to decide.
A wedding ceremony in Germany is actually no more than a blessing because you have to have been married by a registrar first to be eligible to have a ceremony in church/mosque/synagogue.