I think stampedes occur when people don't have patience to wait for their turn. When people want to rush ahead of others...that is when chaos begins. We see this in almost every place in India where there is a big queue. The solution is....the mentality should change i.e., learn to be patient. For example, when Indians come to US, they stand nicely in queue without pushing others. Of Course, the lines are very small here compared to India. Again, this takes us to the issue of over population.....Hmmm! What to do???
