Let someone go first

Was at the store today shopping. I had on of those smaller carts but I did fill it. The store had one checkout open, so I decided to go through the self-check out as those are faster for me. There was this lady who came behind me. I noticed she only had a thing of pre-made fried chicken. Told her she could go ahead of me as I see you only have one item. She smiled and thanked me.