Dubbing does have a place in modern chicken breeds, but it is a minimal one. Sometimes it is done for cosmetic reasons, but most times, not.
Dubbing is most commonly done on breeds of chickens that have abnormally large combs. These combs can be detrimental to the bird's overall health. For one thing, overly large combs have a bad tendency to flop over to one side, covering the chicken's vision on that side. If the animal is free-ranging, that is a huge disability, especially for a rooster, who is responsible for spotting predators and sounding alarm for the entire flock.
Another reason that dubbing is done is, as previously mentioned, to prevent frostbite on birds. It is much better to have the comb removed under sterile conditions and with the proper medical attention afterwards, than to have it slowly turn gangrenous and rot off of the bird (and yes this is how frostbite works). The impact to the health of the bird is very positive.
A third non-cosmetic reason for dubbing is an effect that is still being felt in Game birds, who have been bred for centuries to be aggressive with one another. Having a large comb and wattles is a neon sign to each other, and tearing and savaging of the combs is common. Dubbing is a lot safer and more healthy to the bird than having it ripped off by a dirty beak.
While I understand that many view dubbing to be cruel, and are quick to dismiss the practice, it is, like many issues, a practice that has many sides to it. It is worth understanding it fully before standing so firmly on one side or another.
And while it is valid to simply give up on breeds that require dubbing, it would also be equally valid to want to preserve our heritage through preserving the breed, and to work on the standard from the inside out. To wit: breeding for smaller combs, and joining the breeding club and rousing support for a change in standard from within.