Then why are Primary Schools allowed to subject the future of our children to this system leh?
At that age you have to assume everyone is equal. If based on merit, there are only a few criteria that can be used, some that have been used here are even questionable like affiliation to the school. Does this really mean anything as to whether the child will do better in this school or in another school? Others like distance from home seem more logical.
After sorting out by all these criteria of merit, balloting becomes the only method left to decide the remaining applicants. At this young age, you do not want to stream them by intelligence as they are still developing and at varying and ever changing rates. So no entrance exams for them.
But not all schools need to go through a ballot which is only needed in the most popular schools. Unfortunately most parents think alike and get attracted to these same schools.
The way to change this attitude of the parents is to remove as many as possible the hurdles that mark the next stage of the child's life. An early streaming means that getting into a school that achieves the best for my child becomes very critical. If exams are taken just as an assessment of progress, not as a critical passport to the next of the child's life, parents will be less kiasu and practical reasons will predominate for their choice of school e.g. the distance from home. That way, the locations of schools can be planned to sync well with the location of the population.