I have a feeling that losing $10 on your deal would have been a small price to pay for the reputational damage. Personally, if someone quoted me the wrong price I wouldn't require them to honor the quoted price, especially if they said they were sorry for the mistake but unfortunately couldn't honor the price. Most LFS are running on some pretty thin margins and in this economy it's a wonder that they can stay afloat.
However, I would certainly expect a sincere apology and not..."i dont know why your making such a big deal about this,"...this is why they would lose my future business.