Wei and Cashier dispute

Wei and Chong went supermarket one day to buy some glossary . In the supermarket Wei looked at the good which on display and decided to purchase 3 bottles face creams which were on offer . She took the bottles to counter and paid for it .As they leaving the supermarket , the cashier come up and told them they have to return the good . In this case whether a not Wei return the bottles to cashier ?

For my own opinion , Wei have the right not return the good to cashier. According to contract act 1950. In this situation the contract is binding . This legal principal is clearly illustrated in "pharmaceutical society of great britian Vs boots cash chemist Ltd " on the beginning , Wei looked at the good display on is only the invitation to treat , when Wei decided to buy the face cream . The contract is not yet make between Wei and cashier .This situation change when Wei took the bottles to counter and she paid for them, then only the  contract is make .

In this case , cashier have no right to took back the face creams from Wei . In order for the face creams to get back from Wei , supermarket might offer Wei good compensation in order to get back face creams from Wei.