To Food Truck or Not to Food Truck

originally, i thought to start with a table, then a cart, then a food truck, then a small cafe, then bigger, etc. and grow the business that way if it took root. but watching the truck scene in downtown durham makes me wonder if there is enough density to eke it out as a food truck operator working full time (40 hrs) or part time (20 hours). in fact, i said, jokingly, to yoyo, that an Onion headline might read "Second Wave of Food Trucks Finds There is Not as Much Money in Food Trucks as Previously Believed". I know the tacquerias on Hillsbourough have been doing it for years, but I wonder what their revenue/margins are like. I know that Farmhand was trying to come through the NC Mutual building downtown where I work for several weeks (1x per week), but I doubt they did more than 40 lunch covers per meal. At $6 a sausage, they might net $125-150 after employee wages, ingredients, and overhead. Kind of a hustle. How many trucks do you think that Durham's density can sustain? I know that a truck like Farmhand can kill it at a bigger event (as they have at Fullsteam or Motorco), but those events only come once or twice a month. Does Durham have the density or desire to support a food truck culture akin to LA, NYC, Chicago, or Portland? Does anyone know more about truck economics in Durham or the Triangle in general?