When docking was still legal (to the majority) but the law had changed from any layperson being able to do it to a qualified vet, many breeders had to seek out a vet that was willing to do this procedure (this was often done through The Council for Docked Breeds) and whilst pups were docked they would have their dew claws done too.
I know that an awful lot of show people, now that they no longer have the tails docked leave the dew claws intact too.
Florence was born a month after the ban came in and she has her dew claws as well as her full tail.