Three studies recently published speak to the nutritional content of away from home meals and the public's lack of awareness of just how 'unhealthy' those meals can be.
   I am going to give you a brief bottom line summary from the research.  The citations for the studies are:

Block, J. P., Condon, S. K., Kleinman, K., Mullen, J., Linakis, S., Rifas-Shiman, S., & Gillman, M. W. (2013). Consumers’ estimation of calorie content at fast food restaurants: cross sectional observational study. BMJ, 346. doi: 10.1136/bmj.f2907
Urban, L. E., Lichtenstein, A. H., Gary, C. E., Fierstein, J. L., Equi, A., Kussmaul, C., . . . Roberts, S. B. (2013). The energy content of restaurant foods without stated calorie information. JAMA Internal Medicine, May 13, 1-8. doi: 10.1001/jamainternmed.2013.6163
Scourboutakos, M. J., Semnani-Azad, Z., & L’Abbe, M. R. (2013). Restaurant meals: Almost a full day's worth of calories, fats, and sodiumJAMA Internal Medicine, 1-2. doi: 10.1001/jamainternmed.2013.6159

    In the Block study, researchers found that American's continue to underestimate the amount of calories in quick service (counter service) restaurants, in general, but do an especially poor job estimating calories in restaurants perceived to be healthier (e.g., Subway, Panera Bread).  There was a slight difference in how accurate people were based on whether they were adults, children or teenagers, but everyone underestimated the total calories by about 200 calories.  Most interestingly, teenagers and adults were off by 300 and 400 calories, respectively, for Subway meals. The more calories a meal had, the worse people did at guessing them.  By the way, the average calorie content for a meal at KFC and Wendy's was less than the average calorie content for a meal at Subway.  Adult meals from McDonald's, on average, had more calories than Burger King (606 v 530).  This study supports the need for onsite, in your face, nutrition labeling.  The restaurants in this study are covered by the national menu labeling law.
   The Urban team reviewed the calorie content of meals at restaurants that will not be covered by the national law. They studied independent or small chain restaurants (less than 20 stores nationwide), that were within 15 minutes of downtown Boston (USA).  They included 9 popular types of restaurants (e.g., Italian, Indian, Vietnamese, American) in their study.  They determined which 4 meals were the most popular at each establishment and focused on those.  They ordered each meal, with one side item, and brought the food back to a lab.  They determined the exact number of calories in each meal through chemical analyses.  They also determined the number of calories per gram of food (energy density).  In their paper, they provided the average total calories and density for each of the 9 restaurant types. In some instances, they were able to make a direct meal comparison between an independent, local restaurant and a national chain.  For example, a lasagna dinner at a quaint Italian bistro in Boston, compared to a lasagna dinner at Olive Garden or Macaroni Grill.  The average calories for one meal at all but the Vietnamese restaurant was more than a third of a days worth of calories!  The average calorie content (1327 kcal) was HIGHER than the average for chain restaurants covered by the law (890 kcal)!  The highest averages of the local restaurants were at the Italian, Indian, Chinese and American restaurants.  Italian was the worst - 1755 calories for an average meal.  That is just about what I consume in a whole day but  I split it up so I can eat about 8 times.  The average amount of calories for a Vietnamese meal was 922 and they had the lowest calorie per gram.  When the researchers matched meals to a national chain, there were still more calories in the independent restaurants, but the difference was less.  Bottom line - too many calories in restaurant foods and your local restaurant isn't doing any better.
   Lastly, and quickly, Scourboutakos looked at more than just calories in 24 sit down chain restaurants in Canada.  Her team found that for breakfast, lunch and dinner - each average meal provided over 50% of a days worth of calories, total and sat fat, sodium/salt and trans fat.  If you ate your 3 main meals at these restaurants, you would consume over 3000 calories in one day and I bet you are not Michael Phelps.

   When did it become necessary to count calories at a restaurant?  When we started eating at them several times a week instead of several times a year.