I think there might be a commonality here – a number of them seem to be located in Australia (with one in India and one in the UK) – a whois check shows a few AU contacts and an AU-based whois privacy guard, so I can't be sure, but the do seem to be oddly clustered, IMHO.
My bet would be that some third-party web firm/designer has sold all of these companies a "unique design" and more than likely most of them are unaware of the origin of the design, much less the other sites with the very same design.
Perhaps – but then why the geographic coincidence/clustering I noticed in the sites cited by the author? It certainly could be just dumb luck, but it seemed unlikely.
My bet would be that some third-party web firm/designer has sold all of these companies a "unique design" and more than likely most of them are unaware of the origin of the design, much less the other sites with the very same design.