Your premise is fairly shallow - chemistry isn’t magic, and there haven’t been any studies even indicating a weak potential for harm. The fatty acids are broken down completely in a way that’s very well understood, chemically, leaving no unexpected metabolic pathways - unlike, for example, fructose. The biggest problem with canola that I’ve found is the harm it does in the form of smoke, and the chemical changes it undergoes at high temperatures (read: deep fried stuff.)
Again, I respect your right to choose, but please refrain from labeling canola oil as even potentially harmful without bringing evidence to the table… I’ve searched, and continue to search, for any solid indicator.
Also, erucic acid isn’t toxic, or even dangerous. It’s just another omega 9 fatty acid, which when it’s the majority of an oil (pre canola rapeseed,) makes it markedly unhealthy (because of ratios, not because of its nature) and makes it more susceptible to oxidization, and thus rancidity. The reason canola wasnt used for so long was simply the reason humans do everything else - economics. It didnt store well, it was hard to process, and tasted like crap because of the gradual oxidization.
Take the time to dig into the subject, and don’t rely on second-hand writeups, blogs, etc. There’s quite a collection of studies out there demonstrating it’s safety, and not any that I’ve been able to find that demonstrates even a weak potential for harm, even long term. You have to rely on human studies, because animals have very different metabolisms, digestive processes, and even cell behavior that can be affected by plant oils (not just canola.)
You definitely don’t have to. It’s just cheap, and there’s no substantive reason not to, given all available scientific evidence.