Joe,
No, in the UK it would still be perfectly legal to shoot ducks at night with a punt gun, the boys just don't do it.
Over there it's considered almost sacred, the few folks that still do it are looked up to by most wildfowlers as carrying on a nearly gone tradition.
A lot of their punt gunners were cut from a different cloth than most of the markethunters here in the US. There were books written about the sport by Sir Ralph Payne-Gallway and Colonel Peter Hawker, both famous shooters from the UK. Sir Peter Scott, the famous wildfowl artist, was a punt gunner in his youth.
WAGBI, their version of Ducks Unlimited, was started by punt gunners, mainly Stanley Duncan and Gallway.
It's just a different game there than here and always has been. That's why they can still do it and we can't.
Destry
P.S. to Will: How could a .410 be a punt gun?