Exactly, they didn't force you to buy it. They didn't change or cross off the expiry date.
I agree that the store should put the expired stuff away, and they do accept your full refund.
We always check expiry date before purchase. We will not buy it if the item is too close to the expiry date and we may not able to finish it by then.
Or some items we buy as enjoy tonight for 30-50% off at Loblaws or NF. We check expiry date and if we can finish it today or tomorrow. We don't mind getting it aslong as they looks fine.