Im not sure if its an old wifes tale, but I was under the impression its illegal to deny a sale at an advertised price?
As an example, when I was a teenager working in a retail store, I can remember selling a pair of jeans really cheap because we had tagged them wrong.
They should really honour your sale and then fix their mistake. To answer your question, IMO its not wrong to ask.
In Australia, not sure about the US, but it is completely legal to refuse sale at the advertised price.
Advertising is not considered an 'offer' under contract law, it is called 'an invitation to treat'. At this point it is the customer that makes the offer and the seller that accepts. So the contract is not enforceable.
Obviously the ACCC has regulations in place tol limit these representations to only accidents. But they won't make a seller enforce the contract.
I've used this exact 'invitation to treat' arguement against customers in my ****** retail job at Lenards where I scrouge up the money to study Law.
No idea about American law though.

