@ossobuco,
I haven't eaten from these newfangled food trucks. Admittedly sometimes the food seems kind of interesting; but, never to a great enough degree that I have wanted to try it. A truck hawking grilled cheese sandwiches is unlikely to lure me in as I am to finicky when it comes to those. If they are selling other items, it may interest me for a few seconds; but, not necessarily long enough to pull me over and get me to buy.
The Great Food Truck Race (Food Network, 3 series so far), has interested me, mainly because I like watching competition shows and I like food shows; however, it hasn't made me want to wander about looking for a food truck. It would take something really special to get me to want to try one of them.
I also have concerns about sanitary conditions.
In a conventional restaurant, deli, food place, the money exchange is between the customer and someone not handling food. In these trucks, a naked hand handles the money then goes off and handles food. There doesn't seem to be any hand wash before they handle more food.