My Mother in Law purchased Shrek Third today from Tesco Instore. It had a price tag of £19.99 but when she got to the till they said it came up as £26 something. My Mother In Law then went to customer services who gave her a refund, they did this because it had a sticker with a lower price on it. However they also gave her a refund of the difference, which meant that she only actually paid £14 something for the game as they had refunded her over £12 altogether.
She's a better bargain hunter that me lol!