Two reasons come to mind, and both applied in my case last year: 1. Diversification: the vast majority of individuals owning pre-IPO shares almost certainly ho

Two reasons come to mind, and both applied in my case last year: 1. Diversification: the vast majority of individuals owning pre-IPO shares almost certainly hold options, and in tech companies at least where regular employees get these options few of these individuals are likely to have a large, diversified portfolio. 2. For those same individuals, it's often a life-changing event. (In my case, I went from servicing 6-figures of medical debt and 5-figures of student loan debt and contributing the minimum to my 401k to a 7-figure net worth with income producing, debt-serviced assets.)