This summer, I took a tour of America and stumbled upon this program in a couple of cities: Bicycle Benefits. The concept is bike users put a sticker on their helmet and participating restaurants and stores give discounts and free items to consumers that bring in their helmet and show the sticker. Boston and a couple of other city bike-share programs provide a sticker with the membership.
One major criticism by public health advocates of bike-share programs is the increased rate of biking without helmets. Incentives like this sticker system may increase helmet use- but I doubt a lot of people are studying it (free idea grad students!). This system also seems to benefit businesses by bringing in additional consumers and benefits everyone by taking cars off the road. The only losers seem to be anti-bikers.