Let someone go first

I always let people go first through doors and narrow spaces, etc. Recently, a girl in a supermarket who had been three people in front of me, realised that she'd forgotten something whilst she paid for her groceries. She then popped back round the supermarket to get the item and returned to the queue behind me. When the lady in front of me was due to be served, I asked her if she minded if the girl went before both if us as she only had one thing and had nearly been on her way home. The lady willingly agreed and the girl moved in front of the two of us, thanked us and paid for her item. Things like this always make me feel more human.