Boo, maybe you need to target your market. Perhaps you should try and make your product as healthy as possible, if that's what people want. Start with a whole grain bun. Find an organic dog or veggie dog. Find organic condiments. Feature local-grown veggies. Offer fruit juices and healthier types of chips. Go to Whole Foods and see what they have.
Create a niche, then exploit it. Put out flyers at all the spas, etc. Get press coverage as CO's first "Healthy Hot Dog Stand". Few people don't like hot dogs, they just know better to not eat them.
I would do it, but people around here eat crap.