I get infuriated here in the Uk when I am served by emotionless faces who appear to look at me as an annoyance there to make their existance a little more difficult. One of the reasons I fell in love with Turkey is that on the whole they are very attentive and excellent at customer service.
I agree with Scunner, selling good quality produce just isn't enough and if the good lady happens to have a face that would turn milk sour then I'm afraid all is fair in love, war and business. I have no idea why this lady appears miserable to the point she appears to offer poor quality service but she can only ever be wrong to project that on to her cash paying customers