Lots of companies perform rigorous assessment tests for high profile or high paying jobs. IT is not the exception.
I don't know if you're suggesting that interviews should assign actual tickets in an interview, but that seems nearly impossible to do in practice. I've never got back work from an interview or assessment that was anything near production code - nor would I expect to. It's to get a sense of the level of their real world coding skills are since there is such a variance between developers.