I am a big promoter of customer service. When I am in the position of providing customer service, it is part of my personality to smile and say thank you and make the customer feel appreciated. I have good cutomer service skills, but I also expect it in return. Why is it that 9 times out of 10 I'm the one saying Thank You to the cashier when I buy something? I don't get why, when I'm standing at a counter for 10 minutes waiting for help, the employee makes direct eye contact and keeps going about her business, without even a "I'll be with you in a minute". I despise rude people (waiters, cashiers, drive through workers, whoever) and I have on occasion brought it to the attention of the manager when they are unmistakably rude. Employers in service industries should not tolerate people who cannot deal well with customers. Rudeness or indifference should never be OK.
On the flip side, I try to make a point to let people (and/or their manager) know when they've been kind, patient, helpful, etc. I have been guilty of calling up my health insurance company, angry about the fact that despite my numerous phone calls and lots of time wasted, they still haven't resolved the problem. But there are certain people who are really good about diffusing that kind of anger, and they 'kill me with kindness'. In the end, I always thank the nice ones for being so helpful and kind.