Yes. We (myself and other half) went through the purchase process a few times buying 15 pairs of trainers (for ourselves and children). They charged us £0.00 for the trainers and £8.50 for postage each time.
I took a number of screenshots that clearly stated that the trainers would cost £0.00 with the shipping cost of £8.50 using the term 'buy it now'. And received the confirmatory emails.
A few other friends also went through the process and purchased from them.
How would they be able to prove that it was an error rather than a marketing stunt? I understand that the offer was running for a number of days and 300,000 orders placed before they pulled it?