What Cruelty?
When animals are bred for the pet store industry they are bred as cheaply as possible. The goal is PROFIT, as such any legal (and some illegal) short cuts are taken. Animals are warehoused and bred over and over and over. Very little "people time" is given to them, as such they are not well socialized and are prone to behavioral problems. Other acts of cruelty are common in the industry.

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Puppies, For Example
Puppies are bred in "Puppy Mills". They are not bred for genetics, not for intelligence, not for longevity, not for confirmation... only profit. They breed to produce quantity, not quality.
Because small = cute, they often stunt dogs with poor nutrition. The parents are generally kept in small cages, sometimes stacked on top of one another. No additional expense is occurred. They are fed minimal amounts of cheap food. Vet attention is only given as a last resort, or sometimes not at all. It is all about spending as little as possible so they can make the most profit.
The moms are bred over and over, their bodies given no time to recover. They are killed or abandoned when they are no longer useful. The majority of puppy mill adults are not adoptable, they are not socialized, and may have never even walked on grass. They are mentally unstable because of the substandard conditions of their life, and are generally unsafe as pets. They are not house broken.
The pups suffer from poor nutrition, often have worms, and may have other mental problems as a result of being raised with very little human contact, or in filthy conditions. Puppy mill pups have a higher rate of coprophagia (eating their own feces).
When you buy pups from a pet store you are NOT "rescuing" them - you are condemning hundreds of other dogs to live in horrid conditions. You are rewarding people for mass breeding of pups. A store will always deny using Puppy Mills, but a reputable breeder would NEVER sell to a pet store. Indeed Puppy mills are illegal in many countries, but they still exist.
How Can You Stop Puppy Mills?
Puppy Mills are illegal in many areas, the problem is that the stores simply buy from other areas, or from brokers who buy from the mills, and keep the location of the mill secret. Pet stores turn a blind eye to where the pup comes from. As long as it is priced right.
Thus the ONLY way to stop Puppy Mills, is to stop buying pups from pet stores. If the stores can no longer make a profit by selling pups they will discontinue to sell them. Educate others not to buy from stores. If possible do not shop at stores who sell pups.
If you are in an area where Puppy Mills are not illegal you need to encourage your politicians to push for legislation against them. Talk to your local animal shelter to get them involved.
Other Animals?
YES!!! Other animals come from "mills" too. Not just pups. Purebred cats, birds, rodents, etc. All come from mills when sold at pet stores.
Rodents are particularly easy to breed in plastic crates, and this is generally how they are produced. Crate upon crate upon crate. The parents and the young do not get any handling, and are therefore not very friendly.
Birds are often bred in mass situations. They may have been removed from the wild in other countries and brought to the store - this practice is illegal in some countries, but legal in others, either way it results in amazing stress and loss of birds.
Where to Buy From
In addition to buying from Reputable breeders (which can be found in Magazines, or at shows, or from word of mouth) a prospective owner can find a pet at their local animal shelter, SPCA, or rescue. If you go to a private home to look at pups (for example) for sale, and the facilities or dogs are in bad condition, do not feel sorry for the pups. Do not reward the seller. Instead call the local authorities for pet care and report the substandard conditions.
Vegetarian Cats
Another act of cruelty in the pet industry is people who are trying to make their cats, who are true carnivores, into vegetarians. This is total cruelty and will cause your cat a lot of health issues. Cat nutritionalists agree that most of todays "acceptable" foods don't even have enough meat in them to meet a cats nutritional needs, many use corn as a cheap filler. If you want a pet that is a vegetarian, get a rabbit.
Legal Pet Mutilation
Legal in SOME countries I should ad, illegal in others. I am referring to procedures like declawing in cats, ear and tail docking in dogs. Some forward thinking countries have outlawed these elective surgeries. Others still allow them, and veterinarians often willingly do them, after all, they are paid to. There are alternatives to declawing a cat, including Soft Paw, claw protectors.
This is a cruelty that you can stop - become aware of the side effects of such surgeries before subjecting another animal to it. Do not wait for your vet to try to talk you out of it, they are in a conflict because they are paid to preform these surgeries.
Euthanasia
Every year millions of kittens and pups are euthanized because more are born than there are homes for, the simplest way to end this is for people to spay or neuter their pets. People are ignorant to think their kittens found a good home, many "free" kittens do NOT find good homes - and those who do, take up homes from others needing homes. If a person owns an unspayed female, cat or dog, they should keep that pet indoors until they can get her fixed.
Why Stop Cruelty?
Well, obviously for the sake of the animals involved. An animal who is treated cruelly is more likely to be a problem animal, a threat to its' owners and others. An animal who is treated well from the time it is born, will usually be a good pet.
There are a small number of people who believe that because "some" cruelty exists, that ALL pets should be banned. They hear of one horror story and use it as a catalyst to get people to protest the ownership of all animals. Some animals benefit from being pets and if all pets were banned, we would have to euthanize millions of animals.
GREAT ARTICLE!