I've heard that blow-aways can snap a cello's neck, even in its case whereas you may not have done too poorly with a soft case that was light and therefore you could hold close to you. In fact, my $660 repair (which could have been a lot more) was a tipover in the parking lot because a wind-gust blew it over.
I thought the same way about hard cases that you do. That they offer far more protection. What is amazing is to hear all the stories of blow-away cases and broken cellos, including a rather prominent one discussed by a professional cellist on twitter two weeks ago.
I have always used a hard case. That being said, I have only one experience to justify the hard case. I was leaving orchestra rehearsal, opening my back door, when a huge gust of wind knocked the cello onto the ground. I have no doubt that my hard case prevented a disaster. So it may never happen again, and it may never happen to you, but I'm awfully glad my cello was in a hard case that day.