And then there is, in some areas, the big issue of whether the fish has the skin on, or whether it has been taken off.
In parts of East Yorkshire this is the mark of a cultural divide which can stretch to the proportions of the United/City or Everton/Liverpool football ghettoism.
The native population eat fish with the skin on- incomers from foreign parts (by which the natives mean the West Riding of Yorkshire) like the skin removed.
So you need to know if it's a local Chip shop or a Wezzie Chip shop. (Wezzie being West Riding)
Cod and Haddock were the fish of choice, with Haddock being seen as more refined. Neither group would even consider eating "that rock salmon muck like they 'ave down south" and freshness is a serious business.
I've seen a notice in a chip shop in Scarborough, apologising for the use of frozen fish, because severe weather had prevented the boats from going out.
It was the weekend of the Hurricane.
Scarborough is North Yorkshire- a different thing again from East and West Yorkshire!
These local preferences and practices are the real modern folklore and they are still going on underneath the radar of the folklorists.
Cheers
Dave