“Hello”, a smile, and “thank you”, would make my shopping (my banking, my dining) experience very rewarding.
I know I’ll find myself recommending you to others. Good, friendly service gets etched into my brain (which, by the way, is hot-wired to the hand that holds my wallet) and I do tend to want to share good news.
Positive experiences get my loyalty juices flowing and I’ll find myself returning because you’re polite and you try hard on my behalf. I know I’ll return to your establishment if there is some indication that you care.
It is when you are surly, abrupt, and I feel unwelcome, that I find myself looking elsewhere for the services and products you provide. Little things like ignoring me, avoiding eye contact, talking to co-workers, answering…