I'm assuming this was a larger plane? I've been denied boarding of a smaller plane due to weight. It's kind of scary when you think about how careful they have to be.

Air Midwest flight 5481 crashed in part from being overweight. There were 21 passengers aboard. I think the airline was using an average weight per passenger of 160 pounds, calculating half men and half women or children at 180/140. Problem is people tend to weigh more than this these days. The flight was actually made up of almost all grown men and ended up being 500+ pounds overweight. The very heavy suitcases had been put in the back making it tail-heavy.

The pilots could have dealt with the weight problem had their not been a maintenance error. Anyway, if in doubt they are welcome to keep me off!