Given the task definition and input, reply with output. In this task, you're given five sentences, numbered 1 through 5. Your job is to generate a title for the story that makes complete sense. The title must be short, with less than three words, use simple language, and include the main topic of the story.

Sentence 1: Sally bought a coffee at her local coffee shop. Sentence 2: On the receipt was a survey. Sentence 3: For completing it, Sally got a free donut-which she redeemed at lunch. Sentence 4: Then she was given another receipt with a survey on it! Sentence 5: Sally realized she could get limitless free donuts!
Coupons