I used to be a cashier. I just wanted to tell you what she might have been thinking since I've been on the other side of that stupid cash register. Being a cashier is one of the worst jobs you can have. People yell at you just because you are there, or they treat you like you're invisible. Then, you get people who want to talk to you too much. Then, if you are a woman, you tend to get hit on too. That can be uncomfortable when you are just trying to do your job. Some cashiers are unusually friendly, and are bored so they strike up a mini conversation with a customer to break up the monotony. Even me, a shy girl, would sometimes have some little thing in common with a customer, and make small talk for the brief amount of time I was ringing them up. It just helps the day go by when your feet are on fire, and your drowning in a sea of people. Occasionally, I received a nice compliment. That always brightened up my day, but it did get very annoying if that compliment was followed up with a request for a date. If you want, give her an innocent compliment, and leave it at that. She may have thought you were cute, but did slip in the 'ol boyfriend, so she's not looking for anything.