Pups and adult dogs may find traveling very stressful. It will be alot more stress free if they travel in a familiar surrounding. Again they will see the crate as a safe place. You won't have a dog jumping all over the car, making it safer for both humans and dogs. If your dog has travel sickness, it will be a lot easier to clean from the crate than it would from all over the upholstery.
Not all people are dog lovers and your dog may need some Control when friends come to visit. Not everyone likes to be jumped on and covered in drool. The dog can easily be placed in the crate until he calms down or the visitor leaves.
If your dog needs to stay with friends or family members during holidays. Then he will feel a bit safer in his crate and the friends may be glad of a little peace if they are not used to having dogs around.
Most hotels won't allow dogs unless they are to be kept in a crate.
Pups can get up to all sorts of mischief when left home alone. Chewing carpets furniture, not only is this dangerous to the dog but it is going to be very dangerous for the wallet when everything needs replacing. Worse they can chew through electrical wires and you can come home to a fried pup or burnt down home.
One thing you must never do is, give your dog in to trouble then send him to his cage. He will see this as a place he is when he is bad and will associate it with you being angry. The crate must be a fun place, a rest place, a safe place, give him toys, treats and you can even feed him in his crate. When he is older this will no longer be necessary as he will have learnt that is his happy safe place. His den. A place to call his own.
A huge crate is not necessary, but get the biggest you have room for. Your dog should be able to stand up and turn around easily and have no problems when lying down. Buying a bigger crate to start will save you having to buy a larger adult size one later on. Shop around the Internet as prices and quality vary considerably.