How about this then ... give up smoking and get £12.50 in vouchers to spend at the local supermarket!!!
BBC NEWS | Scotland | Tayside and Central | Cash incentive to quit cigarettes
They do have to prove it by the carbon monoxide test that they havent had a ciggie .. Thing is though when you give up smoking you will have the money you used to spend on fags which if you smoke 20 day £35 extra in your pocket ... so buying healthy food shouldnt be a problem should it ...