card viewing etiquette

[aba20]

I asked to see a person’s card’s after a big no limit hand and he responded that I should not be allowed to see them unless I thought he was colluding. He felt that me asking to see them was very rude. I was just wondering what the B&M etiquette was on this since you can always see online.

PS I did search for this and couldn't find anything. If this has been discussed a link would be great.