I know how Sears feels. When I was younger I worked for a large retail store where people would regularly bring me expensive items and tell me they found them in a dump bin or on the discount shelf. A lot of them cited some fictional law that said I had to give them the discounted price. I spent many wasted hours of my life explaining why people couldn't buy a pair of $100 brand name sneakers for only $10.
Sears is facing a similar headache after they accidently listed the 16GB iPad 2 for $69 on their website. The retail store blamed a third party seller for the mistake, and informed people who bought the discounted device, that they wouldn't be honoring the false sale price after it went viral on Facebook and Twitter.