The Cash back offer

This being a festival season, in short shopping season almost all consumer based enterprises
r upto making the most of it, why shld the base of this consumerism- "credit cards" be left behind.Almost all of them have come up with various unique cash back schemes.
From the ICICI bank stable, there is an interesting offer:

If u happen to make a pay transaction(ie shop, no other mode is eligible) for Rs 2000 or more thru ur ICICI credit card u b'come eligible for cash back offers and the summation of the Authorization Approval Code(AAC) that u get on ur transaction slip decide the percentage of ur profit.

Now this AAC is 6 digit no. and to get 100% money back the sum should be more than 51
The max possible value of the sum of AAC digits is 54(999999)
The max possible combinations are 28 so the probability is 0.0028%

Similarly for 75% cash back, the sum shld be 0-5
the max possible combinations are 161 n the probability is 0.0161%

for consolation u r assured of a 1% cash back everytime!!!

but the ad screams only "100% Cash back offer" in bold!!!

btw i m eyeing another interesting festive offer by Shoppers Stop, which states that

"Since I am a First Citizen Card Holder, if I or my frenz do a shopping for

Rs 30000!!!, i get a diamond pendant" (the offer is valid till Dec 31)
the catch : shopping done in facet shops n via gift coupons r not counted.

So if 15 of u out there do a shopping for atleast Rs.2000 @ Shoppers Stop using my card no
i can make use of the offer.
hey is there neone out there abt 2 shop in Shoppers Stop do get in touch with me n get my Card no. n help me win a best fren (of course diamonds!).