Is it the bars, restaurants and night life that attract young professionals or vice versa?
Lets take food trucks for example, because they are mobile and can demonstrate where the market is viable by where they set up on the reg as it's profitable for them. They do well around Calandros in Capital Hts, Southdowns, etc, but no so well outside of those areas for the most part, so they stick there. I've seen them at events outside the city where thousands of people were and did squat, and yet you would have thought they would have destroyed business considering the product they are offering for so little, but the patrons either walk on by or look at them like they are from outer space.
It's not the business. It's the people. The cool people move to an area, the kind that get it and support cool stuff, and the business will be there in a second to support them. Guaranteed.