???

According to an estimate (my own estimate by observing the placement statistics at some Indian engineering institutes websites), nearly 65-70 % of all engineering graduates join IT companies. Interestingly, the institutes have only 10-15% seats for computer science/ IT streams. So I was wondering why we teach so many students Electronics, Electrical, Mechanical, Chemical, Civil etc subjects when we know they will eventually end up working for some IT company. Why not have 70% seats in the computer science class and the remaining 30% seats shared by other branches?