First of all, years of "real socialism" have fostered a hate toward the rich and any private business owners, so making it illegal wasn't that far fetched. However that was shut down by Constitutional Court for a while.

Secondly, EU did ATAD, so the law was updated to be compliant with the constitution, but it was still ambiguous AF.

Finally, it is a part of the racket - since it is so ambiguous, it safer to petition for paid advance tax ruling.