Forbidden Fruit

I popped into a supermarket recently, with the intention of buying only a couple of items, so I didn't think it necessary to get a basket. As tends to happen when scouring the aisles and their half price offers etc, I ended up with a large handful of items. One such item was a couple of grapefruits which I'd put in a bag and hung over my forearm to leave my hands free for other items. When I got to the checkout I unloaded my items onto the till and paid for them as per usual. It was only once I'd left the store I realised that I was still holding the bag and hadn't paid for the grapefruit!

Now I was faced with a moral dilemma of sorts - should I go back to Somerfield and cough up for the grapefruit or simply just keep walking, and later on take a bite from.. forbidden fruit?

What would you have done?