We have a lolalty card and we do not moniter what they buy or what they get free we just think it is good customer service. I used to go to a coffee shop before I owned one and would use their card I always got a large latte when I was due my free drink they told me I got a small coffee for free. I didn't take the coffee and I never went back. We do have a few customers who play that game buy small coffee get large latte but on the flip side we have converted some coffee drinks to latte drinks on a daily basis. The more they try a latte the more they want a latte.