How did one of my classmates back in high school not realize Kahlua contained alcohol?

Back in the early 2000s this girl had a kahlua she was drinking on in my anatomy class. Someone saw her and started talking and i guess the teacher heard and found out and told her that that was alcohol and my classmate claimed she didn’t know it was an alcoholic beverage. Said she got it from her mom. I think she thought it was just coffee. It was a different looking bottle of kahlua. Luckily the teacher was cool about it and just told her to throw it away. I just randomly thought of this again and had always wondered if my classmate was full of shit not knowing it’s alcohol lol. She sounded like she was telling the truth and was worried in her voice when the teacher confronted her.