To be fair, I don't think you're considering the fact that the person who was doing the greeting (Salvation Army worker) was someone who was collecting money. Sometimes people don't feel like donating, are broke, or have already put money into another kettle. They don't want to respond because they know they will be asked to chip in some change and they don't want to feel obligated. I mean, I would at least say hello in return as I walked past, but many people will stay silent out of feelings of embarassment or guilt for not putting any money in the kettle.
.....Kelly
