....but your not taking into account or understand some the following.
1) They have to pay personal in Customer Service to deal with the customer.
2) Items must be checked to be sure it's not damaged, IS the correct item and has all accessories. Saying this is daunting task considering you have 1000's of products to understand and recognize is a tremendous underestimate. Lots of monetary loss happens at this stage
3) Must be repacked, re stocked and setup with special pricing codes/data base and employee understanding.
Overall retailers lose money on restocking items and just saying it's a "racket" (racquet is used in tennis

) shows a complete lack of knowledge of basic economics.