Barbaric manners

At 07h30 this morning at Spar Geduld Springs, while serving me, the cashier unashamedly, and with no consideration for me, sucked back her snot. When I told her how gross and bad mannered it was, she arrogantly told me its her sinus and she can do nothing about it. That sound kills any appetite for breakfast, and lunch and dinner. For a store who serves food, it is barbaric.