Bad customer service

Went to this store to buy talkies for my son on 23rd Dec. Timmy was the shop assistant on the floor. We were not offered assistance my sister tried to ask him if they had the talkie she had in her had in the store he ignored her. Another lady walked into the store and he walked towards her to assist. As he walk back I stopped him and asked why we were not offered help to my surprise he advised that he was not employed to offer assistance to customers and that the other lady called him I then said but my sister also spoke to you and you ignored her. He walked off and carried on with other customers. I will not go back to that store and I would like to know from sports scene what us the role of their shop assistants if it's not to assist customers?