A corporation as a savings vehicle is NOT unfair.
There are no pensions and benefits.
How do you compensate a doctor for 10 years of university, when there is no income, no contributions to CPP.
The public sector have years more income, that they pay less tax on.
Consider lifetime income accumulation.  
These small business people often take many years before they have excess income over expenses.

The public sector does not pay tax on:
Their advantages of Indexation
The fact that their pension is based on on the highest 4 years of their income.