It is another stupid over-generalized slogan that actually does no damn good to get clarity or sanity in the economic sphere. If enough were more clear the bad practices of current banking would not be put up with. There are parts of banking that are needed and good and parts, especially as perverted by deep government/bank partnership, that are completely fucked and need to change. But killing all bankers wouldn't get you to better. It is cathartic nonsense and worse.