In the past, why did Harry and his friends visit Mr. Tillian after school?

Since Mr. Tillian owned a candy and nut shop, Harry and his friends visited Mr. Tillian after school to sample the available confections. The boys either bought roasted peanuts or penny candy from the huge bins.
Mr. Tillian enjoyed having Harry and his friends at the store after school hours. As time progressed and the boys reached junior high, however, Mr. Tillian began to see less and less of the boys at his store. Since the boys were now older and had more pocket money, they chose to spend their money on video games, records, and fast food.
Later, Mr. Tillian bought himself a parrot in order to stave off his loneliness. Interestingly, the parrot became the means for Harry to eventually realize how much his father had missed his presence at the store.