Some people are shomer negiah only in public. I have a friend who will only hug me when no one else is around. When he first hugged me I was quite surprised, since he is Orthodox and shomer negiah in general.
Another friend decides when he wants to be shomer negiah.
Sad but true: I once worked with a girl who was wondering if she was still shomer negiah because her shidduch date touched the end of her ponytail by accident.