Oh you utopian, myopic fools.  Once you have been turned away by US Border guards, your identities are now on a security list which will deny your entry into the States for a very long time.  Think of it, after you graduate you may apply for a position with the wholly owned Canadian subsidiary of a US multinational corporation and the critical job interview may take place in the US - you won't get in, you won't be considered for the job.  Educational, commercial business conferences, a stop-over flight in the US enroute elsewhere are out of the question.  You have limited your options and it will cause you grief in the future.