You can't tar them all with the same brush.....there are people that trial that only breed every few years to continue to get good stock, and never sell to pet homes....I am one of them.....and my dogs will work a full day on a shoot the same as the non-registered workers that you seem so keen on....and regularly do 3 or 4 times a week....
The reason that pedigrees are important is that it is a record of where stock has come from - if there is a particular strength in a dog then people will want to use him/her to continue breeding dogs with that strength....how can you keep a record of tha