I think it's a lot more likely that the teller was lazy than than it is the bank had an official policy of making such recommendations (which is probably what it would take to hold the bank responsible).
It's also possible his flabbergast is manufactured and that he was indeed trying to avoid the reporting regulations.
http://www.nytimes.com/2014/10/26/us/law-lets-irs-seize-acco...
The IRS claims they've stopped: http://www.nytimes.com/2014/10/26/us/statement-of-richard-we...