Err I don't know the nationality of the alleged felons on the Huddersfield canal.
However it is a fact that there are a couple of northern European countries where carp is traditionally eaten at Xmas and Easter (therefore 'a treat', like chicken used to be in the 50's!) and during and 'after the war' it is said that the lake at Coombe Abbey certainly suffered more than somewhat (well - it did start off as a 'stew pond' for carp to provide the medaeival (sp?) monks suppers, after all!) (I believe there was a POW camp nearby ....) and 'more recently' I do know for a fact (it was in the papers and people were indeed prosecuted, 'ignorance of the law' being no defence!) that an ornamental lake just off the ring road in Coventry just by the Cov and Warwick Hospital, stocked with some very large carp, took a bashing too!
Pete is an avid carpist and follows all the forums, commercial lakes everywhere all follow the 'no kill' policy and A LOT of European lakes (in France especially) took a severe bashing with persons allegedly from these other N European countries visiting and having a good feed! Some of these huge carp can cost around £1,000 each to buy for your lake, the anglers are willing to pay for the sport (shades of E Hemingway LOL) It appears that the 'actual anglers' have caught on by now - however, this intelligence has not always filtered down to the 'common man'.