If you look at it from a net benefit perspective—if you use the public sector instead of the private sector in a case where you can charge the same kinds of prices, but it just means that the people providing that service are making more money and receiving better benefits—is there not a net benefit to the community?
Even if in terms of GDP you have the same effect, there's a benefit in terms of its distribution and making sure that it's getting into the hands of ordinary working Canadians instead of being held in the hands of whoever happens to be the owner of the private sector player that comes in.