Given the price of concertinas these days - in fact the price of concertinas in the 19th century too…I think they might count as posh instruments. Obviously the Anglo was designed to to populist and the duet was for pros but… they still cost much more than most other instruments. Check out eBay and you'll be paying £3,000 for a decent anglo - for which you could buy say…6 hohner pokerwork melodeons.
By the way Guest - I wasn't going to say that but…yes. :-)