Canada refund rights: does every store have to take back a change-of-mind purchase?

No. Canada’s Office of Consumer Affairs says businesses are generally not required to accept returns simply because the buyer changed their mind; store refund and exchange policies often control unless the item is defective or another statutory right applies. Provincial and territorial rules can add protections. Official source: Office of Consumer Affairs. Guide: https://getinstantlaw.com/ca/topics/consumer-rights