I think schools and doctors are just frantically trying to find ways to stop this fat epidemic, which we do have. I also think that we should be able to see our kids' ribs, and we are so used to seeing overweight people (like myself - I really need to lose 20+ pounds, if not more), that we don't even realize how heavy our friends and family are. My "skinny" kids (75th % in height, 45th% in weight) are probably the norm decades ago, and yet people comment on how skinny they are. My chubby ds (90th % in height and weight) was told by the pediatrician that he's fine, although his BMI is "at risk" - he can pinch an inch, and does have belly fat. He is not big-boned, just looks like he is.
I find so many parents who label their children "solid," when in fact, they are fat. However, if the whole family is "solid," they just don't see it. Several years ago, there was a tragic tourist boating accident, because although the boat didn't go over the occupancy limit, it was an old boat, and the occupants were hundreds of pounds over what the expectancy was decades ago. Scary.
Are you talking about Lake George? If so it was found that they did have too many passengers, 3 times more than it should have. The capacity rating was wrong due to things that had been added, but it was never tested again so at one point ot could safely hold all those passengers, but at the time of the accident it wasn't capable. So, it did have to do with the weight of the passengers, but because there were too many, not because they were overweight or "solid".