By saying "No customer is statistically insignificant" Dave means that... 1) every person deserves a good treatment by service producers. 2) it is not statistics that companies should be thinking but people. 3) companies' attitude to statistics is painful for customers like him. 4) anyone can damage a company's reputation through social media.

By saying "No customer is statistically insignificant" Dave means that... 1)  every person deserves a good treatment by service producers. 2)  it is not statistics that companies should be thinking but people. 3)  companies' attitude to statistics is painful for customers like him. 4)  anyone can damage a company's reputation through social media.