[nostrademons]

If purchases are public, where can I get the data so I can build my map of the economy?

[yummyfajitas]

You can get the data by hanging out in target and watching what people buy.

On one occasion, some kid in a CVS gave me a high five after seeing me buying a mega-pack of condoms while carrying a bottle of whiskey. Did he violate my privacy?

[nswanberg]

You used to be able to get aggregated data for free at data.mint.com, but it looks like they have removed that feature.

http://www.mint.com/blog/updates/mint-opens-up-its-data-see-...

[unreal37]

You have a pocket full of credit cards, debit cards, and loyalty point cards. Every air mile you get is paid for by someone selling your purchase history to another company for marketing purposes.

It's not public for anyone to grab. You have to pay for access to the data. But if you can pay, you can get the data.

[nostrademons]

Data that can be had for a price, but not by anybody, is usually called "proprietary", not "public".