The gong show is entirely of Air Canada's (and other airlines) making.

By charging for luggage they put an economic incentive into carrying on luggage. By making passengers wait extreme times in YYZ and YUL to get luggage (really, why must one wait 45 minutes for luggage in these airports when third world countries and former soviet republics can get it out in half the time?), they add more incentive to carry on.

Adding these incentives and continually increasing passenger density without increasing storage space creates competition for space.

Thus, people get up to get in line early because if they don't, they know they will be screwed out of space and have a more difficult flying experience.

Everyone is simply acting in their own best interests. Those headaches that the staff endure are entirely because the airlines are giving benefits to passengers who are willing to fight for their spot in the queue.

What I hate most is not being able to get to the priority boarding because of the gate lice, or what's worse, cutting off someone else who is trying to get to the priority boarding who I can't identify as a friend or foe in the boarding battle. So sorry to cut you off fellow business class dude, I thought you were a louse ...

So, due to their basic misunderstanding of economics, the airlines built this problem of people rushing to board. They need to then come up with a system which will manage the problem... they need to put up a cattle corral and make people walk through it, or they need more ticket checking and "sit down please" instructions from staff, or some other creative solution.

People who are boarding out of order need to be sent back 100% of the time on all airlines and that will encourage a bit more sitting down, until that happens though people will know their best chances are by getting up and crowding the gate.