Having worked at a kennel/doggy day care facility and now at the SPCA, I saw a lot of silly things that owners did with/to their dogs that were completely unnecessary.

• Carry them in purses. I know you bought a tiny, teacup dog that was extremely over bred to become that size in the first place and that, yes indeed, it will fit inside your bag. But it's a dog, it needs to and wants to walk and run and sniff on the ground.
  • Some people have coddled their dogs so much, though, that they don't even know what to do as dogs anymore when given the chance.
• Paint their nails. I get that you see your dog as an accessory and want it to look cute. But your dog doesn't give a shit.
• Buy them a bigger wardrobe than many people have. If you're going to spend that money on your dog, use it to give it a better quality of life by getting it more natural food and taking it on an outdoor excursion or something. It may look cute, but again, your dog doesn't give a shit.
• Let their dogs kiss them on the lips. I have seen owners crouch down and full-on make out with their dog. A lick on the cheek is okay now and then but allowing your dog's tongue to enter your mouth is disgusting. Do you know how many dogs I see eat their own poop everyday?
• Don't discipline them when they jump on people. Would you let your child clamber on strangers? I hope not.
• Don't discipline them and train them, in general. Dogs thrive on structure. They want to be lead and shown what is right and wrong. They are much happier with a routine.
• Are scared of their own dog. Dogs have extra keen senses and can easily pick up on your mood. If you are scared of them, believe me, they know it and will take advantage of it.
• Don't exercise them or take them on significant walks every day. I don't know how many times I've seen people just walk out their front door with their dog, let it pee, then bring it immediately back inside. What a boring life you're giving your dog.
• Feed them "people-food". I have seen many an obese dog that was on multiple bone and joint medications. Do you know why your dogs' bones and joints hurt? Because of all the extra weight on its frame from your over-feeding.
• Don't spay and neuter them!! This is huge. There are millions of homeless dogs that get euthanized every day. By not spaying and neutering your pets, you're just contributing to a growing, uncared for population.
• Don't socialize them. You've got to expose your dog to other people and especially other dogs at a young age otherwise there is a good chance you will have a shy, aggressive, potentially dangerous dog on your hands.
• Dye their hair. Your dog has no say in whether you dye its hair and I think it cruel to use chemicals to alter your dogs appearance because you're bored or so that it can match your handbag or something.
• Keep them in crates all day. If you don't have the time to commit to your dog or at least have the money to pay for someone to care for it while you're away, then don't get a dog!
• Use electric-fences. I've never understood this. Do you not like the appearance of a fence or something? Electric-fences are not safe. For one thing, if a dog wants to leave bad enough, they can break through the shock barrier if they have to. And also, electric fences do not keep out other wild animals or people who wish to do your dog harm. I have seen fearful dogs with abuse in their pasts go to homes with electric fences where there are then traumatized after they feel that first shock.
• Drag them along on their leashes. I can't stand when people get impatient and don't let their dogs take a few god damn seconds to sniff the ground and be a dog. They just keep pulling them along so they can get the walk over with.
• Leave their dogs in the car. Especially when it's hot! If it's hot for you, it's twice as hot for your dog.
• Don't keep their dogs secure during 4th of July celebrations. Working at a shelter, I can say that the day after 4th of July is one of the busiest days of the year for us, with reports of missing dogs skyrocketing as well as the number of dogs turned into us a found strays. Fireworks TERRIFY most dogs. On the 4th of July, keep your dog safe and secure inside!