When I was 20 years old I had a summer job in Austria and I was asked my religion--because I was under 21 I didn't have to pay the tax. There were a couple of guys from England working at the same place and they rejected being classified as "Evangelisch" because they were Church of England, not Lutheran.
Yes,after I posted I used Google and found that Austria does collect a religion tax.I don’t know how many mainly Christian countries do it but I know I had heard of it being done even before I read this piece.