Scold Misbehaving Shoppers Publicly

Do it as gently as possible while still making your point. But whenever a shopper violates the norms of courteous store behavior in front of other shoppers, clearly call out the offense and offender. Researchers at University of British Columbia and University of Alberta find that unless you do the scolding yourself, the other shoppers may do it, leading to problems.
     Too often, people will cut in front of others who are waiting in a checkout line, ravage the tray of free samples so that none of the good ones are left for others, or unnecessarily create a huge mess at a merchandise display. The British Columbia/Alberta researchers saw that other shoppers who witness this happening are tempted to punish the offender. The observers do fear embarrassing themselves, but also have trouble looking the other way. All this is to your disadvantage as a retailer for two reasons.
     First, the mental turmoil inside the heads of these shoppers preoccupies their thinking, if only for a brief time, and preoccupied consumers buy less. Worse yet is if the miscreant bounces from one offensive behavior to another as the shoppers and store staff are watching.
     Secondly, you don’t want fights breaking out in the aisles of your store.
     There are reasons the offender is likely to be forgiven by the others, so that there’s less need for you to intervene:

• If it’s obvious the consumer has been treated unfairly or experienced adverse circumstances while trying to complete their shopping. One example in the research is of an airline passenger who just before completing check-in is told the computer has gone down, and the passenger later butts into line at the security screening. 
• If the shopper has a negative physical attribute which is perceived as being beyond personal control. The example in the research was of someone who has a visible medical condition. 
• If the offender is of high status. Rank has its privileges in the civilian as well as military world, it would seem. 

     Store décor also can make a difference. Researchers at Harvard University and University of North Carolina found that adults behaved themselves better when in environments where childhood playthings—such as teddy bears and crayons—were around. In the study, participants carrying out business around the playthings better respected the norms of courteous shopping and were less likely to yell at each other if somebody violated the norms.

Click below for more: 
Prime for Good Behavior with Family Cues 
Show Respect in Front of Customers