Because there could be a coin split and people are worried about that.That's exactly we all are anxious. We fear splitting bitcoin into two.
So price might go up or fall really hard. Soft fork ? Sounds great but too many greedy people don't agree (I really don't know much why ).
To my mind, it's the matter of experience. Experienced users see much further, than newcomers, so they consider hardfork just as a "working moment"