Bell Canada and other big Canadian corporations have direct access to credit report records. If not paid, they will spoil your credit report. A credit report is essential in Canada for things such as credit cards, mortgage, car loan, and sometimes even for renting an apartment or home. With a poor credit report score all this would become more expensive or even unavailable.
Customer service provided by large corporations in Canada is sometimes absurdly poor, but you can't do much about it because there are simply no reasonable alternatives.
Same goes for a credit card, you can ask you ban for a reverse charge and disallow any further charges from that company.
This credit report thing is a real pain in the US/Canada, from what I see in various posts and comments.
This is a French perspective where such a reaction would be normal. I did it twice, one company called to say I am in the wrong, I asked them to please repeat so that I can record that for the lawsuit.
They hung up and never called back.