If you are a regular , the salespeople will begin to recognize you. Some will even start to notice the things you like to see and things that you may wish to purchase. I also noticed that the elderly frequently visit the malls. They talk to various employees of the mall and become familiar with what's going on. I even began to tell when a salesperson from one store was making reference to another salesperson from another store.
Salespeople have their own language.
A customer will enter a store and one of the salespeople will give the other salesperson a gesture, as if to say whether or not the customer will make a purchase. This is how they would know whether or not to really work hard when helping that particular customer. The third reason, which I recognized through my observations, was that people come to the mall to meet new people. Teenagers may do this more often than other age groups. They may not have any intentions to buy any merchandise, because their main objective is to find a date.