Bear in mind that I am the board's resident stats geek...
A lot of people just aren't curious about the technical side of the hobby. I have absolutely no quarrel with them. There is a lot to be said for keeping it simple, jamming half a box of Super X in your jacket along with some power bars, and a half-frozen milk jug of water, and slipping out of the house early enough to be in place before daylight.
To some of us, this hobby is a grand engineering experiment.
To us, a chronograph is an extremely useful instrument, probably the most accurate and repeatable instrument we can access.
If your loads are exceeding "book" velocity, they are almost surely exceeding "book" pressure. That's a good safety application.
If you are developing longer range loads, it's good to know your MV so you can set your elevation at 100 yards so that it will be close farther on out. That's a time saver.
If you're doing benchrest level shooting, a chronograph is a big help in developing process consistency. That's a competitive advantage.
If all I shot was a 30-06, 270, or other common chambering, and if my only need was to be ready to hunt, I don't think I'd need one. But for the things I like to do, it's a useful tool.
