Mr. Speaker, anyone who wants to cross the border to the United States has to go through customs. Having pre-clearance in Canada not only streamlines the movement of goods and services and makes it easier to get to all U.S. airports as a domestic rather than an international traveller, but also ensures that the Canadian Charter of Rights and Freedoms is applied on Canadian soil, even within American pre-clearance zones. That is an added layer of protection that Canadians would not have going through customs in the United States.
In the House of Commons on February 22nd, 2017. See this statement in context.