Its not about professionals per se, but should be about the risks they take and investments in their own business they make.  For example, canadian physicians who work in hospitals are essentially employees - even if they are techinically fee for service - they assume no risk - pay no rent - employ no one - buy no equpiment (the hospital does all that) - why on earth should that have access to the same benefits as a small corporation?  The doctor in his/her private office - who does take the risks outlined above - they should have the benefit of a coporate structure.   See the difference?