another alternative for excersing of oppies

There are quite a few posters stating the substantial benefit of sending cheque to excercise oppies, claiming that if u bought 0.5c oppie and if price move to 15c, then u make 4.5c.... this is true, but why should u be bother to send cheque in when u can buy on market at cheaper price????

Instead of excercising oppies, let look at below scenario:

- if u have 1mln oppies: then instead of sending cheque in, just buy the head at what ever price below 10c, if the head is more than 10c, then excercise to ur capable financial ability, if not just abandon the idea of excercising oppies b/c it is obvious that u can get it cheaper on market and the ability to liquidate immediately if u want to....

I just don't understand why someone should urging u to excersise when u can buy the head is cheaper? should this be report to ASIC for investigation of manipulation.....??? But then, i guess most investors' IQs are high enough to solve this simple maths....