Yes, u r right. In fact it should be greater than Rs. 30,000 (considering many brokers charge 0.03% for intraday). But what if somebody trades hugely on exposure ? And when u take it as delivery ? Then also they charge Rs. 9. Now calculate with your delivery brokerage! It will be hugely beneficial to those who trade for very short term, BTST, etc.
Now for intraday, the beauty lies elsewhere...
If u trade in very low priced scrips, suppose u buy 1 lakh shares of Sanraa Media at 30 paisa and sell it 31 paisa, your broker will not charge u @ 0.03% but 3 paisa per share. Now think... u pay 6 paisa as brokerage for buy & sell i.e. u won't be able to trade in such scrips because its difference between lower filter to upper filter is not more than 6 paisa! In RKG u will get Rs. 960 profit in just 1 paisa profit margin (deducting Rs. 18 brokerage and taxes).
Earlier I wondered how these type of scrips generate so much volumes when Intraday trading is not profitable considering 1 paisa brokerage also. Then I came to know there are brokers who offer fixed brokerage / unlimited brokerage plan.