True.There par example you spent 4+6$,okay i could give you the bonus.But i will have to do the same thing for everybody.If someone buy for 20$(40K of bonus),he can ask for the bonus.Then,if he buy again for 20$(40K of bonus)he could ask for a 40$bonus in overall.Each of his bonus will be added,and i would loose a freaking loads of money.I could do this if each peoples were just buying one time,but alots of peoples here are regulary customers..:3