I had the same response. It should really read - sincere sales increase sales - thats the model. Whatever is considered to be the next sincere thing will be emulated by marketing and ruined.
Sincerity under payment has to be taken for what it is. I expect and appreciate to be treated nicely when going to a restaurant but I'm under no illusion that it's because I'm going to pay for it, otherwise I doubt all that people would be cooking, serving and cleaning afterwards with a smile in their face while I sit there saying thank you.