<rant>
Eastern Girl: I'm not surprised at all to hear experiences like yours considering the pre-board screening contractor at Pearson is Garda, along with BC, Edmonton and QC, other than Vancouver and Montreal. For anyone who doesn't know about Garda and its reputation in the private security, let me put it in hockey terms: they are the late '90s Tampa Bay Lightning of the industry. Worst of the worst, it just does not get any worse than that. The person who screened you likely makes the minimum wage in Ontario and was on a huge power trip. Calgarians will know what I'm talking about regarding Garda's quality control with their employees if they've been to the Stampede in the past few years.
You can voice your concerns to CATSA (the crown corp. who gives out these contracts)
Here, and
with any luck, maybe those fiberals will stop wasting money on advertising and give out a decent contract to a respectable security firm. 
MMM: the YYC is run by Servisair, they only do airports like Aeroguard but they are European based, Group 4 pulled out a few years ago IIRC and really, they weren't all that bad.
As for CBSA agents I would rank Wancouver's as the worst bunch of asswipes in the country, or North America for that matter. I've had some very unpleasant experiences with Tampa and New York's US customs but none of them could touch YVR's Canadians with a 10 foot pole. My advice to everyone is if you're not Caucasion, it's better to fly thru LAX or NYC back into Calgary on an international flight. Calgary on the other hand probably has the best custom staff I've dealt with around the world, but I agree with fotze, avoid the Caucasion middle-aged women agents.
</longer than expected rant>