Hilarious story.
I had a similar pressure washer problem. They would not replace it and randomly accused me of leaving it out in cold weather and therefore it broke. Total junk product, but if you sell it, you should be held accountable. I never go for the "not our problem" response.
I left a dead battery, still well under warranty, but not honoured, right in front of their front sliding doors, but wouldn't have the guts to do what you did.
I do have thoughts of a much more stealthy response, like flooding their customer service lines, their website, or using technology to cause the same effect as you did...to tell everyone that Canadian Tire is a low class store who will use any legal loophole to screw their customers.
they will go bankrupt. they used to survive on the fact that they were the big store, but now they have low end products, often seconds or products that other stores won't sell. This is particularly true of batteries, tires AND their business is going to Walmart, Home Depot and Costco. Those stores have found a niche and should survive.
My customer service experience was similar. Thank you, yada, yada, we will forward this to a specialist, yada, yada, then the rejection of my claim for one of a shopping list of excuses. They could say anything, really, and unless you're willing to go to court, or camp outside the store, you have no chance of success. Small claims court is a viable option because it only costs customer about $75 to file a claim, and by the time they get their lawyer involved, it will cost them $5k or more. If the claim is reasonable, they would not consider awarding costs to CT so its very little risk for a reasonable claim. I would urge any and all pissed off customers to spend the time to do that, and a positive outcome might well be an offer to settle it right away.
Personally, I'm gonna try all legit means to inform web shoppers that the store sucks. This means finding ways to get sites like this one at the top of search results for people looking to buy, or by flagging it on shop bot type site. Wish me luck. My object is to damage sales by $500k over the next two years.