Aside from being the location in our yard that gets the most direct sun, there are other reasons why I've gone in the direction of container growing. First is the ability to control the quality of the soil that the plants grow in. After growing tomatoes in our main garden for more than 10 years, soil borne diseases were increasing to the point where a substantial portion of each year's plants were dying prematurely and yield per plant was decreasing at an alarming rate. By using pots that can be bleached each season and using sterile soil less mix, the plants have a significantly better chance at making it through the season sufficiently healthy to provide a decent crop.
Second, and this pertains primarily to eggplant and peppers, my theory is that these heat loving plants enjoy having their root zone baked in the hot sun. I've found that yields are far higher with container grown plants than when grown in the ground.
Finally, having the plants right outside my garage door provides an ability to make closer and more frequent observations of the plants and fruit. On my way out the door to work, and following my return home, the plants are right there in my face, making it easy to spot problems and progress.
Of course, no gardening activity works perfectly....but I will save the issues of container/driveway gardening for another blog entry!