Local Business versus Chains

Local businesses... I have studied economics, and yet I'm still in the gray. +jobs is still more jobs.. yet I understand peoples comments especially Dr. Mikes.
Pizza may be a +sum -sum, and I agree with the adding of manufacturing jobs.

So back to my main topic, Local business vs Chains. What is the best way to bring in new businesses and what kind of jobs can be brought in that won't harm other existing businesses. I'm curious since I would like to open my own business someday.