Not sure if this one will be able to fly here. I've seen it approached in different places where it got out of hand pretty quick but in light of the Thread about the use of Heavier and bigger shot size, I'll give it a go. Moderators please pull fast if it takes a wrong turn at too high of speed.
First off. A long shot for self is one taken at an honest 40yds. Over that is beyond my skill level and equipment which is geared to less than 30yd shots with birds hovering like GoodYear blimps over the blocks. If they aren't going to fully commit, generally I'll not be taking the shot. That's my rush of it all.
To me Scraping is when a person is continually shooting at birds beyond thier skill level or equipment capabilities and missing / cripping birds. Them doing this for whatever reason, be it trying to increase thier bag by doing as they've seen someone more capable be succesful, the thrill of hearing the gun go off with the excuse of having a bird in the general vicinity, or ignorance. For some reason this catagory has a high percentage of folks who don't realize, don't care, or rationalize about the effect they are having on the birds, surrounding hunters and hunting as a whole.
Long / Pass shooting, on the other hand, when being done by a person with a skill level and equipment that matches the approach, is nothing less than any other accepted method of take for waterfowl. All the good Long Shots I know take into consideration the birds and fellow hunters. They frequently take thier birds with a bird to shell ratio that beats mine taking 20yd decoying shots. They've earned thier stripes of skill and knowledge on the clay instead of the ducks which is IMO where it needs to be kept (the practice part.). It's no different than accomplished calling, jump shooting, sculling, dog work picking up other's lost birds, etc. It's an art of it's own.
Whenever this topic has come up as the theory has evolved that decoying ducks / geese is the only acceptable method I think about Dove hunting. Decoys and sometimes calls are used but the majority of the time taking them is done with pass shooting. Sometimes at loong ranges. Some of the longest shots I've ever seen made on real birds were on doves during the national trap shoot at Kingsburg over Labor Day weekend. One of the in between pastimes for some of the guys used to be huntin down at the bottom of the Range or out by the Gum Trees. Lots of consistent honest 90yd shots connecting at high speed. How come it's nowadays considered OK to do that with Doves but not waterfowl if this method is applied properly?
Years ago in CA there was an un-official place provided for pass / long shooters on most CA Public Areas. The dreaded "Firing Line". Both Long Shots and Scrapers would have at it. It concentrated a large portion of folks who preferred this type of shooting leaving the rest of the place, for the most part to those that wished to work birds etc. It also provided those that wished to work thier dog an opportunity to make a couple of passes several hundred yards behind the Line and pcik up crips. (A good / bad thing.) One would say this reason, lost or cripped birds, made the Line evil. It was this thinking that caused changes to be made to the system. IMO it was the ill equipped Scrapers that caused this, not the Long Shooter. I witnessed the difference from afar many, many times. Are the Firing Lines really honestly gone? The assigned blinds across the front of the north Closed Zone (used to be the Firing Line. Folks lined up on the road between Lots A and B) at Delevan are still mainly a pass shooting situation. I'd venture the majority of birds taken from those blinds are by pass / long shooting. If a person told me they were successful at working carp (snows) into decoys from one of those front blinds I'd have a hard time believing without seeing. Same holds true for the Northernmost assigned at Sac and the original ones at Los Banos WA. The slot we called The Point at LB way back when (not sure of the number now) doesn't even have any place to work a bird. It's still a top producer. How they doin it? I know of one well established club that Long Shooting is the main way they take thier birds. All of them agree. The place has been a duck magnet since time immortal and a person could work to commit birds any time of day during the season. They simply grew bored with working and taking birds, pass shooting provides more excitement to them.
All this just my .02 that all legal existing forms of hunting waterfowl have thier time and place when in the hands of the right person.