Common question here - standard Economist policy is never to name their writers and correspondents, except very very rarely. Their content is published under the name of the newspaper, not the individual author.
Could you please identify the PR for me? I'm genuinely intrigued: all I see is an observation that different kind of bank has an audience outside of its intended audience, an explanation of how it operates differently, and criticism that it is not as different as it makes itself out to be.
“Sin stock” is a commonly-used phrase in finance and does not imply an ethical opinion on the topic by the user of the term, merely that ethical opinions are often held on the topic by the public/investors at large.