Do lot of people stay for that long at one company?
Also note in some states where it's after 10 years you actually start accruing the leave after 7 years and if you leave the company prior to 10 years you get paid out for the amount of long service leave you have accrued. Again from the article at 5 to 10 years tenure is around 18%
Even with low participation it would be political suicide to make long service leave harder to gain or even try to take it away. Probably why Victoria actually made long service leave kick in after only 7 years.
It all depends upon what your priorities are. Mine are working to live, with a minimum of ratrace.