banks have all this info - its already published to 3rd parties via rewards schemes and tbh i wouldnt be surprised if the banks sell it as well. retailers resell it... none of this data is private. in effect i am publishing it already. but as you say, i would gladly have it all posted online for anybody to see if it meant financial transparency for all.

edit: perhaps i wouldnt like my bank balance published... that may make some individuals targets. in thinking about it perhaps i would prefer financial "transaction" transparency. then we would have to guard against huge cash transactions tho somehow. its clearly a difficult topic but its also the source of a lot of the worlds corruption and misery.