The way all the gangsters who AREN'T connected to Viggo react to John Wick: they all love and respect him! The crew at the Continental is excited to see him again! And unlike other action films, you get a sense it's less because he's a badass to be feared and more because they genuinely like and respect him.
Every scene with John and his dog Daisy is adorable, which makes it even harsher when Daisy gets killed.
When John takes the pit bull home from the veterinarian's office at the end of the film. And the last shot of him and the dog is them walking down the same bridge where his wife fell ill. It may have been the start of her death, but it was the last moment where John and Helen were truly happy together.
"Let's go home."
A blink-and-you'll-miss-it shot of his cage shows that he was slated to be put down. John saved his life.
Marcus checking in on John at Helen's funeral. John's out of the life, but Marcus is concerned for his friends.
Addy offering her condolences to John at the bar, and remembering his usual drink order. And Winston for paying for it. And giving up Iosef's location at the Red Circle club while doing it.
In particular, the Continental staff being incredibly cordial to John when he returns to their establishment as a temporary home during his Roaring Rampage of Revenge. They seem to be aware of the personal tragedy that had hit John and sympathize with what he's going through.
John appears out of the shadows to get the drop on Francis and his opening line is to ask him for a count on how many guards are in the Red Circle under the guise of asking how much weight he's lost. After getting his number, John gives him the opportunity to walk away unharmed, which he graciously accepts. Francis even thanks John before leaving.
A Meta example: Omer Barnea, the actor who plays Daisy's killer, felt horrible every time the scene was filmed; the moment the director yelled cut, Omer would immediately hug the puppy and cuddle it.