Whatever happened to: "Thank You" after a retail purchase ?

For a lot of stores and for many products, yes, who cares if I get my bread from Store A or Store B. But a lot of people are willing to pay a bit more to shop local, for example, and they want to feel like it’s worth it.

I was especially struck by the camera store example because I recently bought a new camera and I am willing to bet that the OP would have saved some money buying online. People who own and work in that type of specialty store should know that one way to compete with lower competitor prices is by providing a more personal and informative experience for the customer. Part of that is showing appreciation for choosing their store. If the clerk was otherwise helpful and attentive, I would consider that showing appreciation in itself, and probably would have left feeling good about the experience anyway and not even noticed the lack of a final “thank-you.” But if I went to that store and wasn’t treated well, first I would consider leaving, and if I did decide to buy something I’d be a little annoyed (but not surprised given the experience so far) if I wasn’t thanked, and it would probably be the last time I shop there.

The use of the word “favor” there was a response to Jaledin’s post. (I thought it possible that she had misconstructed her sentence, or left something out.)

I don’t exactly think of my patronage of a business as a favor, but I do consider that I’m giving them something that I could choose to give to someone else. I make the choice based on many factors, but attitude and manner toward customers is one.

I do all of that too. As I said earlier here, and have said in other threads, my personal custom and local experience seems to be far above average in terms of number and sincerity of human interactions with retail and service employees. People in my area think (not accurately, but also not without basis) that non-Southerners are just routinely rude in public transactions; the attitude expressed by Runs With Scissors above would be seen as verging on psychopathic.