I have never witnessed a Retailer make a mistake that they didn't own up to...or make you an offer that is irresistable.
Buyer beware. Just because it's an advertised price does not mean you have a competed purchase.
Recently purchased 8 Kurt vises from Hardinge on line for their advertised price. Their on line system accepted my order and gave me a bill of sale for the purchase.
The next day I received a call from Hardinge and was informed that the sale would not be honored at that price. I could pay corrected price or have the order cancelled.
They "would not" honor the sale, or give me any discount for their admitted mistake.
Even WalMart will honor a mistake