The "problem" with Brits is that they live so close to the Sea and have so limited fresh water fishing possibilities that they generally don`t eat anything that does not come from the monger. Even the saltwater lure anglers often practice C&R. They love their "coarse" fishing for cyprinides and perch, generally speaking everything but salmonoids, and are very suspicious about any new predator.
You may invite them to carp fishing, but God forbid anybody does the Carp any harm while they are around- they will turn their back on the mark in despise and never come back. I am absolutely serious. That is actually an issue with respect to imigration and xhenophobia since many east european imigrants have a far more down-to-earth attitude when it comes to pickling quanteties of small, bony fish.
There are some lost forgotten ponds in East Germany where the co-operative once stocked carp for food before being liquidized. Anonymious pictures show fish up to 80lbs. No online posts, no articles, no guides, no exact information - just gigantic carp being caught and treated with maximum care once in a while. THAT would be something to make money of, but they generally do not speak too much English and are not too fond of foreigners, either.