This is standard practice in Australia and has been for many decades. I came across this practice in the late 80's and early 90's and it became even more common and egregious as time went on. At the time, the company I was working for decided to update the employment contracts of all of its employees and we were all supposed to sign these new contracts having these "ownership" clauses in them. I know I didn't and there were many of my collegues didn't as well, but every new employee didn't have a choice. When I hit the 00's and went contracting, I was able to change my basic contract to avoid this on occasions. On others I was not able to get the appropriate changes made. As a contractor though, the "ownership" clause were less demanding. But still, I basically had to stop work on all my side projects (all of them, even outside of the software field) during each employment contract.

These days I can do what I like and don't have to worry about any company interfering. This is a consequence of no longer being employed in any such field.