While anecdotal, I can personally confirm this. my wife LOVES shopping for "the deal" -- it's all a game to her. I tease her a lot because there are countless times where she comes home with widgets that we don't immediately need, but were purchased solely because of their discount %.
For her, something at a low price point to begin with appears cheap, however you take that same item and slap a high MSRP on it with a 50% discount down to that same first price point... now we're talking!
All that you need to do is turn it into a real game by having a website which let's you compete against your friends and strangers for who got the "best deals". Turns it into a game that the retailer is bound to be very happy about.
But people often like games because of the hoops they have to jump through, not in spite of them.
Shopping is a game to many people. You can't "win" unless you get a lower price than other people.