You shouldn't be surprised when people choose not to have LinkedIn profiles. I quit LinkedIn because they were spamming me. They were also selling spamming privileges (or InMail) to anyone willing to pay. The user experience is below average, the groups are pathetic, and recommendations have become essentially worthless.
So really, having a LinkedIn profile isn't obligatory.
You shouldn't be surprised when people choose not to have LinkedIn profiles. I quit LinkedIn because they were spamming me. They were also selling spamming privileges (or InMail) to anyone willing to pay. The user experience is below average, the groups are pathetic, and recommendations have become essentially worthless.
So really, having a LinkedIn profile isn't obligatory.