"7-11 is the best for this as there’s tons of people using it. At one point they had a free coffee every 10 promotion so every time you buy a coffee it was a 1/

"7-11 is the best for this as there’s tons of people using it. At one point they had a free coffee every 10 promotion so every time you buy a coffee it was a 1/10 gamble to get a free one." This is brilliant!