Why do we buy ??

Had a very interesting chat with a friend today about why do people buy ? and what all can a shop do to increase their sales. The problem is definitely well studied .. duh .. it can make better profits for corporation. I remember couple of things I have heard/read

1. In Apple store Steve jobs introduced people roaming with card-reader in hand. Waiting in line people used to put back lot of items they buy now in impluse.

2. All US stores have a return back policy, one of the reason is that people are lazy with a return policy they are more frivolous and carefree in buying and a small percentage do come back to return. (It also have better customer experience and choice factor)

3. Walmart optimize its item arrangement. Six packs are kept closed to Diapers .. A tired man in evening send by nagging wife to get baby diapers usually fell pray to the six pack lure.

4. Ikea has optimized the route in its warehouse for people to follow all the store even when they came just to buy a spoon. They usually end up buying a vase/lamp/bedsheet

The argument I had with him was very interesting, It was clash of two different opinions, He says observing customer behavior in stores can give you these patterns/Ideas and where I believe he is right but as a generic solution mining data for pattern will give us more information.

To his credit .. example 1 cannot be learned by data mining (Unless we have data about how many people take item from shelves and put them back) but example 2/3/4 are coming straight out of data mining approach.