My dog trainer said a crate experience can help if the dog goes to the vet, or to a groomer, where they will be put in a crate. She did say do NOT use it for punishment; should be a good experience for them. my dog goes in her crate sometimes just to nap.

I’ll weigh in on this as apparently the minority opinion.
I’m a big-time crate person.
We crate any dog who is unsupervised.
That means if we’re at work, the dog is crated.
At night, the dog is crated.
Dogs who are unsupervised can cause damage to the house and injury to themselves or even inadvertently kill themselves. We crate for the safety of the home and the dog.
Additionally dogs who are crated at night can be easily located in case of emergency. This is particularly helpful if an outsider, such a fireman, needs to quickly pinpoint the location of your dog.
We do not use the crate as punishment and the crate is just big enough for the dog to lay down and turn around in. Any bigger and they will toilet in one part of the crate and sleep in another.
When someone is home during day hours, which is a lot of the time, the dog is not crated.
While I am probably as old as anyone here (and older than most) I am probably not what you would consider ‘old school’ in that there is a clear line of demarcation between the humans and the dogs in our house.
The dog is NOT a family member. He did not pop out of a human womb, therefore he is not related to us. There is no circumstance in our home in which a dog has precedence over a human. The humans always come first, the dogs are second. That is the pecking order here.
The dog does not eat human food. He does not sit at the human table or sleep in the human bed or sit on the human furniture.
It is not a requirement that every one of out outings MUST include him and most, in fact, do not. If we go out, he’s crated. If we go on vacation, he’s kenneled.
The only outings in which he is included are those outings specifically for him, i.e., his walks or taking him to the park.
He has his own food and sleeping quarters and has a dog bed in the family room (we refer to it as his ‘day bed’) where he may lounge if he chooses to be in the room with us. He is not permitted in the dining room during human meals and we are back to the line of demarcation between dog and human in this house.
When someone is home he does have free run of the house but that is a privilege he has earned with good behavior and it can be taken away for bad behavior, such as chewing or inappropriate toileting.
Even at that, if he is not in our sight we check up on him periodically just to make sure he isn’t toileting on the carpet or chewing a table leg.
Our dog likes his crate and as others have said, will often go there for a little nap (choosing it over his day bed). Previous dogs have been the same and we have had more than one dog who would hide in the crate when he was scared or upset.
I know a lot of people think crating is cruel but it recreates the safe feeling of the den for a lot of dogs.
We have certainly never had a problem crate training dogs and as someone else pointed out, they are a great help in toilet training since most dogs would hold it until they burst before soiling their sleep area.
That is less of an issue for us these days as we don’t bother with puppies anymore. When the dog dies, we go to the shelter and pick out another adult.
But I have digressed. I am very much ‘pro-crate’ and have been for a long time and I will tell you exactly why.
When I was a child we had a dog, Sammy. Sammy was never crated. He was a young dog but he was toilet trained and we always left him alone in the house, secure in the knowledge that he knew better than to soil the carpet.
One day went out and when we returned home, we found Sammy dead. He had gotten his mouth on a full roll of toilet paper on the spindle in the bathroom, tried to eat it and choked to death.
It happened very quickly. We hadn’t been gone two hours. His body was still warm. His bowels and bladder released and the poop and pee were still very fresh when we found him.
Even as a child I realized that we had failed him. We had failed to protect him from himself. We had failed to prevent a completely preventable death. Our poor dog had died in agony in his own pee and poop because we hadn’t secured him.
The problem is that it isn’t just about locking up toilet paper. Dogs can take a million seemingly harmless objects in a house and kill themselves with them. I read somewhere about some poor family’s Chistmas turning to misery when they found their dog had suffocated in a bag of potato chips that he’d gotten ahold of.
You can’t lock up everything in your home so the solution is to lock up the dog.
I know there are a lot of anti-crate people out there. It’s their right to that opinion and their dog is theirs to do with as they wish in their home.
I am pro-crate. It is equally my dog to do with as I wish in my home. I choose to crate and I believe I have presented some very valid reasons why.